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)
548 Calories
19g Fat
75g Carbs
19g Protein
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Nutrition Facts
Servings: 2
Amount per serving
Calories 548
% Daily Value*
Total Fat 19g 24%
Saturated Fat 5g 24%
Cholesterol 47mg 16%
Sodium 3962mg 172%
Total Carbohydrate 75g 27%
Dietary Fiber 5g 17%
Protein 19g
Calcium 43mg 3%
*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 onions and green bell peppers 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 that 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 cafes in Japan. 


  • For the Noodles:
  • 8 cups water
  • 1/2 tablespoon salt
  • 7 ounces dried spaghetti noodles
  • 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)
  • Salt (to taste)
  • Black pepper (to taste)
  • 1/3 cup ketchup
  • 2 teaspoons butter
  • Garnish: chopped parsley
  • Serving suggestion: hot sauce (Tabasco or Tapatio brands for example)

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 the 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 the noodles well and set aside.

    spaghetti in a colander

    The Spruce / Maxwell Cozzi

  4. In a large skillet over medium heat, heat the vegetable oil. Stir-fry the 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 the drained spaghetti to the skillet and toss gently with the vegetables and sausage.

    spaghetti added to the pepper and sausage in the skillet

    The Spruce / Maxwell Cozzi

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

    ketchup added to the spaghetti, sausage and pepper mixture

    The Spruce / Maxwell Cozzi

  7. Mix butter in with the 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. Enjoy.

    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.