Japanese Clam Soup (Asari No Sumashijiru)

Japanese Clam Soup (Asari No Sumashijiru)
Japanese Clam Soup (Asari No Sumashijiru) Koki Iino/Getty Images
Prep: 30 mins
Cook: 15 mins
Total: 45 mins
Servings: 4 servings
Nutritional Guidelines (per serving)
98 Calories
1g Fat
4g Carbs
17g Protein
See Full Nutritional Guidelines Hide Full Nutritional Guidelines
Nutrition Facts
Servings: 4
Amount per serving
Calories 98
% Daily Value*
Total Fat 1g 1%
Saturated Fat 0g 1%
Cholesterol 34mg 11%
Sodium 762mg 33%
Total Carbohydrate 4g 1%
Dietary Fiber 0g 0%
Protein 17g
Calcium 74mg 6%
*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.)

A simple yet classic Japanese clear soup of short-neck clams is not only delicious but is easy to make with very few ingredients. In Japanese, clear soups are known as sumashijiru. This clear soup of clams is called asari (clam) no (of) sumashijiru and pairs wonderfully with any Japanese meal.

Similar to other shellfish, short-neck clams, or asari, have quite a bit of flavor packed within their small shells and require very little seasoning. For this soup, the clams are cooked in a pot of hot water until they open. Those clams that do not open must be discarded as they are not fit to be consumed. The broth becomes a cloudy gray color with delicate flavors of the sea, and that's when we know it’s ready. The soup is seasoned with salt to taste. To bring out the flavors of this delicate broth, very small strips of lemon peel are used to garnish the soup. This adds just enough freshness and acidity to help this soup shine.

If you’re interested, other variations of asari sumashijiru incorporate the use of a bonito (katsuo) based dashi stock, or the use of a dashi konbu (dried kelp) stock, and a hint of soy sauce.

An increasing amount of farmed asari, or littleneck clams, are available at local grocery stores. Typically, farmed clams are scrubbed and sand has been removed prior to their being packaged for sale. Therefore, as soon as you get home they are ready for use. Regardless, if you feel compelled to do so, feel free to soak them in fresh water for up to an hour to remove any excess sand.

If you are using wild clams, scrub them clean and then soak them for up to an hour in a bowl of fresh water to help remove sand. For best results, both farmed and wild clams should be cooked the same day they are purchased.


  • 1 lb. manila clams (live, in shell, about 12 to 16)
  • 5 cups water
  • Salt to taste
  • Garnish: lemon peel
  • Garnish: mitsuba (wild Japanese parsley)

Steps to Make It

  1. Gather the ingredients.

  2. In a medium pot, bring water to boil. Reduce heat to medium.

  3. Add fresh clams in their shells, directly into the boiling water. Cook the clams until all of the clams open. If there are any unopened clams, remove them from the pot and discard as these are not fit to eat. 

  4. While the clams are cooking, using a vegetable peeler, gently peel small sections of the yellow lemon rind.

  5. Serve four to five clams in small soup bowls and pour broth over them. Garnish with lemon peel and serve immediately.

  6. Enjoy!