Masuda (益田市, Masuda-shi) is a city located in Shimane Prefecture, Japan.

Parts of the southern region of the city are within the borders of the Nishi-Chugoku Sanchi Quasi-National Park.

The area of Masuda was part of ancient Iwami Province, and corresponds almost exactly with Mino District, which is mentioned from the Nara period onwards.

After the Meiji restoration, the town of Masuda was established on April 1, 1889 with the creation of the modern municipalities system.

Masuda has a mayor-council form of government with a directly elected mayor and a unicameral city council of 22 members.

In terms of national politics, the city is part of the Shimane 2nd district of the lower house of the Diet of Japan.