To provide a heating cooker that uses members of simple constitutions and can suppress the leakage of a radio wave to the outside and can suppress electric discharge in a cooking chamber.

A heating cooker includes a shield member 4. The shield member includes: a cylindrical shield part 41 which loosely fit to a rotary shaft 30 and comes into contact with an outer surface of a shield box 1 to surround a periphery of an opening 12; and an elastic part 42 which securely brings the shield member 41 into contact with the shield box 1, and has a maximum value of an elastic force smaller than a force to deform the shield box 1.