Zoomed in image of a serving of Tuna Onigiri

Tuna Onigiri

You can make these famous Japanese rice snacks right at home with this easyrecipe! Onigiri (or omusubi) are sushi rice balls that are often shaped into triangles and wrapped in nori or seaweed sheets These tuna onigiri are made with seasoned rice and stuffed with savory tuna mayo filling and wrapped with a crisp sheet of nori.

This recipe stars U.S.-grown short grain rice and comes to us from our friend Megan of @takestwoeggs in partnership with USA Rice and feedfeed.

  • Servings
  • Prep Time
    20 min
  • Cook Time
    30 min
  • Total Time
    50 min



  • 1½ cup short grain sushi rice, uncooked
  • 2 cups water
  • 2 tablespoons rice vinegar
  • 1 tablespoon sugar
  • ½ teaspoon salt


  • 1 4.5 oz can tuna, drained
  • 2 tablespoon Kewpie mayonnaise
  • 2 teaspoon sriracha to taste
  • ½ teaspoon rice vinegar
  • 1 green onion chopped
  • ¼ teaspoon salt


  • 3 sheets toasted nori
  • Furikake seasoning
  • Toasted sesame seeds
  • Togarashi seasoning (optional for extra spice)



  • Cook rice by adding rice and two cups of water to rice cooker or use preferred rice cooking method.
  • Season rice. In a small bowl, mix together the rice vinegar, sugar and salt until combined. Once the rice is cooked, transfer the rice to a large mixing bowl and add the rice vinegar mixture and mix until combined. Cover and let the rice cool.

Spicy Tuna

  • Mix the spicy tuna. In a large mixing bowl, add the tuna, kewpie mayonnaise, sriracha, rice vinegar, green onion, and salt. Mix until combined.


  • Using an onigiri mold, add the seasoned rice to the mold filling it about halfway and press your thumb or a measuring spoon into the rice to create a well. Then fill with about 1 tablespoon of the spicy tuna mixture and then cover with more rice. Firmly place the lid of the mold on top and then release it from the mold. Repeat until all the rice is used.
  • Add the nori. You have 2 options to add the nori. 1) Cut the nori into 4-inch x 1 ½-inch wide strips and wrap one strip around the base of the onigiri. 2) Cut the nori sheet in half and place the rice triangle near the top of one edge and fold the edges to cover the top. Then wrap the long end over the rice.
  • Garnish. Garnish the top/edges of the rice with furikake seasoning, toasted sesame seeds, or togarashi seasoning for more spice. Enjoy!

Recipe Notes

Season to taste. This is your spicy tuna onigiri. You can make it as spicy or non-spicy as you please by adding more or less sriracha to the taste.

No onigiri mold? No problem. If you do not have an onigiri mold, you can easily shape your tuna rice balls by hand placing a sheet of plastic wrap on your work surface, adding rice, tuna mixture, and more rice, and then closing the plastic wrap and shaping it into a triangle with your hands.

Storage: These tuna mayo onigiri are best when served immediately. However, you can store these tuna rice balls wrapped in plastic wrap on the counter for up to 5 hours. If more than that, you can store the onigiri with tuna in the refrigerator for up to 5 days. To reheat, sprinkle some water over the rice and cover with a wet paper towel to steam the rice in the microwave until warm.

Nutrition Facts

  • Serving 1 onigiri
  • Calories 68kcal
  • Total Fat 4g
  • Saturated Fat 1g
  • Trans Fat .01g
  • Cholesterol 12mg
  • Sodium 428mg
  • Carbohydrates 2g
  • Dietary Fiber .1g
  • Sugar 2g
  • Protein 6g