Provided is a taste improver that improves or decreases unpleasant bitterness, astringent taste, harsh taste, bitter taste, or the like that results from potassium salts, magnesium salts, calcium salts, and ammonium salts without adversely affecting savoriness of a food or drink. The taste improver includes a vegetable extract and/or a phospholipid. In the taste improver, the aforementioned vegetable extract includes a vegetable-derived glycoside and/or glycoside aglycone. In the taste improver, the aforementioned phospholipid is phosphatidylcholine, phosphatidylserine, phosphatidylethanolamine, phosphatidylinositol, and/or a lyso form thereof. Arginine is further added to the aforementioned taste improver. Trehalose and/or hydrogenated starch syrup are further added to the taste improver. A manufacturing method of such and an improvement method for the unpleasant bitterness, astringent taste, harsh taste, bitter taste, or the like caused by potassium salts, magnesium salts, calcium salts, and ammonium salts using these taste improvers. A food or drink including these taste improvers.