Spaghetti Napolitan (Japanese Ketchup Pasta)

Spaghetti Napolitan (Japanese Ketchup Pasta)

The Spruce / Maxwell Cozzi

Prep: 15 mins
Cook: 15 mins
Total: 30 mins
Servings: 2 servings
Nutrition Facts (per serving)
468 Calories
25g Fat
48g Carbs
14g Protein
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Nutrition Facts
Servings: 2
Amount per serving
Calories 468
% Daily Value*
Total Fat 25g 32%
Saturated Fat 8g 41%
Cholesterol 45mg 15%
Sodium 2648mg 115%
Total Carbohydrate 48g 18%
Dietary Fiber 3g 11%
Total Sugars 13g
Protein 14g
Vitamin C 47mg 237%
Calcium 75mg 6%
Iron 2mg 14%
Potassium 639mg 14%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

Spaghetti napolitan, also known as spaghetti naporitan, is a Japanese-style pasta dish made with a sauce that is tomato ketchup based. This particular style of Japanese pasta is considered yoshoku cuisine, or Western cuisine with unique Japanese influences. Another term for Japanese-style pasta is wafu pasta.

The recipe for spaghetti napolitan is unique in that sliced onion and green bell pepper are sautéed with either ham (lunch meat style) or bacon and then tossed with spaghetti noodles and tomato ketchup. Finally, it's simply seasoned with salt and black pepper, and served with hot sauce for those who enjoy a bit of spice.

Spaghetti napolitan was created by Head Chef Shigetada Irie at the New Grand Hotel in Yokohama, Japan, shortly after the end of World War II. It was named napolitan, or napoli, after Naples, Italy. It is believed that this recipe was inspired by the spaghetti and tomato sauce dish that the U.S. troops were eating overseas. Interestingly, in order to make Japanese-style spaghetti napolitan properly, tomato ketchup must be used as the base for the sauce and not tomato sauce or puree. 

This dish is quite easy to prepare and can be made in under 30 minutes. It is often served at home, but it is also a standard wafu pasta menu item at cafés in Japan. 


For the Noodles:

  • 8 cups water

  • 1/2 tablespoon kosher salt

  • 7 ounces spaghetti

For the Napolitan Sauce:

  • 2 teaspoons vegetable oil

  • 1 green bell pepper, thinly sliced

  • 1/2 small onion, thinly sliced

  • 1/4 pound sausage, or ham, sliced

  • Kosher salt, to taste

  • Freshly ground black pepper, to taste

  • 1/3 cup ketchup

  • 2 teaspoons butter

  • Chopped parsley, for garnish

  • Hot sauce, such as Tabasco or Tapatio, for serving, optional

Steps to Make It

  1. Gather the ingredients.

    Spaghetti Napolitan (Japanese Ketchup Pasta) ingredients

    The Spruce / Maxwell Cozzi

  2. In a large pot over high heat, combine about 8 cups of water and 1/2 tablespoon of salt. Bring to a boil and cook spaghetti according to package directions until al dente, about 7 minutes. (The pasta will be cooked once more with the sauce.)

    Spaghetti placed in a pot of salted water

    The Spruce / Maxwell Cozzi

  3. Drain noodles well and set aside.

    Spaghetti in a colander

    The Spruce / Maxwell Cozzi

  4. In a large skillet over medium heat, heat vegetable oil. Stir-fry bell pepper, onion, and sausage until softened. Season with salt and pepper to taste.

    Onion, bell pepper, and sausage cooking in a skillet

    The Spruce / Maxwell Cozzi

  5. Add drained spaghetti to skillet and toss gently with vegetables and sausage.

    Spaghetti added to the pepper and sausage in the skillet

    The Spruce / Maxwell Cozzi

  6. Add ketchup and stir-fry spaghetti, coating all of the ingredients.

    Ketchup added to the spaghetti, sausage, and pepper mixture

    The Spruce / Maxwell Cozzi

  7. Mix butter in with pasta, add salt and pepper, if necessary, to taste. Remove from heat.

    Butter added to the Spaghetti Napolitan

    The Spruce / Maxwell Cozzi

  8. Garnish with chopped parsley and serve with hot sauce, if you like.

    Spaghetti Napolitan (Japanese Ketchup Pasta) in a skillet

    The Spruce / Maxwell Cozzi

Recipe Variation

  • Feel free to add other veggies in, such as mushrooms, peas, or whatever you desire.
  • Sprinkle some Parmesan cheese on top in place of the hot sauce.
  • Omit the meat and make it a vegetarian dish.