Unagisaki Knife: The Eel Slicer Used By Japanese Chefs

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Have you ever heard of an Unagi-Saki knife?

Well, unless you cook eel, you probably haven’t! The unagisaki is one of those special Japanese knives chefs use to prepare unagi (freshwater eel).

Eel is a delicacy that is often grilled or added to sushi rolls. 

But to slice and cut the eel, the Japanese use a special sharp rectangular blade knife with a large pointed tip. 

Unagisaki Knife- The Eel Slicer Used By Japanese Chefs

A unagisaki knife is a type of sushi knife that is used to fillet and cut unagi. It has a very sharp and curved blade that allows for precise cuts through the slippery flesh of the eel. The unagisaki is essential for any sushi chef who wants to prepare eel in a clean and precise way.

In this guide, we discuss the features of the unagisaki knife, how it’s used and why it’s a must-have utensil for preparing eel the correct way. 

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What is an unagisaki knife?

To properly prepare eel, you need a Japanese-style knife, known as an unagi-saki.

The knife has a long, cleaver-like blade with a sharp point and is made from high-quality steel. 

These knives are lightweight and easy to use, making them a popular choice for sushi chefs. 

These knives are of superior quality and feature a long, single-bevel rectangular blade that tapers to a pointed end.

Due to their portability and simplicity of use, they are frequently chosen by sushi chefs and Yakiniku chefs when preparing eel. 

So, unagisaki knives are Japanese-style knives used for slicing and filleting eel.

The eel is opened by inserting the tip of the knife near its head and then sliding it along the eel’s body.

The shape of the unagisaki blade is unique and is specifically designed for slicing fish.

It has a short, wide blade with a flat edge that allows it to make clean cuts through the flesh and bones of fish.

The width of the blade ranges between 36mm – 39mm.

In fact, the blade has 45 degree straight angle which leads to a tip which is used by chefs to pierce and slice the eel in a smooth continuous motion from head to tail.

Check out this premium Kanetsuke Unagi-Saki knife to see what I mean:

Kanetsune Unagi-Saki 210mm With Buffalo Horn Bolster Magnolia wood handle G55

(view more images)

The knife’s angled handle is also designed to be easy to hold so the user can hold it in their palm.

The blade looks rectangular when viewed from the side and has a pointed tip at the end. It’s like a small cleaver but the tip is triangular and super sharp.

This allow the user to fillet and gut the eel in a swift long motion.

The blade is usually made of stainless steel like blue paper steel, and the handle is usually made of wood or plastic. 

The blade is sharpened to a razor-sharp edge, making it ideal for precise cutting. 

What is an unagisaki knife used for?

The unagisaki is a specialty eel knife, and it’s used to slice the eel from head to tail.

It’s also used to cut eel into smaller pieces for sushi or other dishes like grilled unagi (learn about Japanese sushi eel here).

Although it sounds like a very specialized knife, the unagisaki knife is a versatile tool that can be used for a variety of tasks in the kitchen.

Its pointed tip and razor-sharp edge can be used to slice other fish like tuna or salmon. 

It’s great for slicing and dicing vegetables, fish, and other ingredients. It can also be used for cutting meat and poultry. 

The unagisaki knife is lightweight and easy to handle, making it a great choice for home cooks.

It’s also a popular choice for professional chefs and the only Japanese eel knife so it’s a pricy knife but worth it for professionally prepared food!

It’s a great tool for preparing meals quickly and efficiently. With proper care and maintenance, it can last for many years.

Why is unagisaki important?

Unagi-saki knives are essential for preparing eel.

The long, rectangular blade of the knife allows for clean and precise cuts, enabling chefs to remove the skin and bones from the meat easily.

Additionally, since unagi-saki knives are sharper than regular kitchen knives, they also make it easier to create delicate slices of sushi-grade eel for dishes such as unagi nigiri.

The pointed tip of the knife also makes it ideal for scoring and deboning the eel, allowing for more even cuts and better presentation of the finished product.

What is the history of unagisaki?

The unagisaki knife originated in the Osaka, Nagoya and Kyoto in Japan. 

The unagisaki knife has been used in Japan for centuries.

It is believed that the design originated from a fishing tool known as an unagi-sakigari, which was used to gut and fillet eel.

Over time, the design evolved into what is known as the unagisaki knife, which was used by sushi chefs to make precise and intricate cuts of eel for sushi.

It’s not known exactly when the unagisaki knife was invented but the Japanese have been consuming eel for many centuries since this type of fish was widely available in the country.

Unagisaki vs Yanagiba or sushi knife

A sushi knife, also known as a yanagiba, is a long, thin, single-edged blade used to prepare sushi.

It is designed to make thin, even slices of fish and other ingredients used in sushi. The blade is usually made of high-carbon steel and is sharpened on one side only. 

A sushi knife is an essential tool for making sushi, as it is used to cut the fish and other ingredients into thin, even slices, which are perfect for sushi rolls or sashimi.

The unagisaki knife, on the other hand, is designed specifically for preparing eel. It has a single-bevel blade that is wider and shorter than the yanagiba.

Its pointed tip allows it to make precise cuts along the length of the eel, making it easier to remove skin and bones.

Additionally, the blade shape of these knives is completely different.

The unagisaki has a wide rectangular blade and triangular tip whereas the Yanagiba has a long, narrow blade.

Unagisaki vs Fuguhiki

The fuguhiki knife is a traditional Japanese knife used to prepare blowfish and other similar seafood.

It has a unique, pointed blade that looks like an arrowhead, which makes it ideal for deboning and skinning the fish quickly.

Unlike the unagisaki knife, fuguhiki knives are usually double-beveled and have a more curved and long blade.

The shape of the blade also allows it to be used for more intricate tasks like scoring and cutting delicate pieces.

While both knives can be used to prepare seafood, the unagisaki knife is specifically designed for eel while fuguhiki is designed for blowfish and other similar seafood.

The fuguhiki blowfish knife is sharper and more precise so it can cut organs without piercing them and releasing the deadly fugu poision.


Is Unagisaki knife expensive?

Yes, most unagisaki knives are quite expensive compared to some of the other Japanese knives. 

That’s because these knives aren’t very popular and not many are manufactured so they’re harder to find.

But these knives, depending on the brand, can range from about $70 to $500 dollars.

What kind of fish is Unagi?

Unagi is a type of freshwater eel that is found in rivers and lakes in Japan. It is a popular ingredient in Japanese cuisine and is often served grilled or in sushi.

What are the features of Unagisaki?

Unagisaki knives are designed to be lightweight and easy to use. They typically have a long, thin blade that is sharpened on one side only (single-bevel). 

Generally, the knife has a blade that is 26-39 mm wide and it has some similarities to a cleaver knife.

The handle is usually made of wood or plastic and is designed to provide a comfortable grip. 

The blade is usually made of stainless steel and is razor-sharp so it can slice through skin and flesh.

How do I use Unagisaki knife?

Using an unagisaki knife is relatively simple.

First, you must make sure that the blade is sharpened properly. This will ensure that your cuts are precise and clean.

Next, grip the handle firmly with one hand while using your other hand to guide the knife along the eel’s body.

Make sure to use a single slicing motion and avoid sawing back and forth.

When finished, carefully remove the skin and bones from the eel before slicing it into perfect pieces for presentation.

With practice, you’ll soon be able to fillet an eel like a pro!

Serve your eel with this beautiful salty sweet Nitsume “unagi” eel sauce (recipe)


Unagisaki knives are an essential tool for any sushi chef or eel enthusiast.

Thanks to its long, rectangular blade and pointed tip, the unagisaki knife is especially adept at slicing and deboning eel.

Its superior sharpness also makes it an ideal choice for creating delicate slices of sushi-grade eel for dishes such as unagi nigiri.

With its long history and unique design, the unagisaki knife is an important knife, especially in commercial kitchens.

Therefore, if you are a sushi chef, eel enthusiast, or anyone who is looking for the perfect knife to prepare eel dishes, then the unagisaki knife is an excellent choice.

Read next: The Complete Guide To 42 Types of Sushi You Find In Restaurants

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Joost Nusselder, the founder of Bite My Bun is a content marketer, dad and loves trying out new food with Japanese food at the heart of his passion, and together with his team he's been creating in-depth blog articles since 2016 to help loyal readers with recipes and cooking tips.