Yamasa Corporation (ヤマサ醤油株式会社 Yamasa Shōyu Kabushikigaisha) is a Japanese corporation founded in 1645 whose primary field of business is the manufacturing of soy sauce and various seasonings. It was incorporated in November 1928.^[1] With its head office located in Choshi, Chiba, it runs two factories in Chiba (located in Choshi and Narita), and a third located in Salem, Oregon, United States.,^[2] where subsidiary Yamasa Corporation USA is headed.

The corporate logo, a ∧ with a サ under it, is a notable example of a Japanese rebus monogram. This is read as Yama, for yama (山, mountain) (symbolized by the ∧) + sa (サ, katakana character for sa).