PURPOSE: To provide the waterproof structure of small equipment where a sufficient waterproof effect can be realized, even in the small equipment wherein thick thickness can not be provided.

CONSTITUTION: A groove 32, where a sealing member 31 is disposed, is formed at a mating surface 13a of one member 13, and a first projection 33 is formed at the bottom of the groove 32 along the longitudinal direction of the groove 32. A second projection 34 is formed at a mating surface 24a of another member 24 in such a manner as to be opposed to the projection 33 formed on the member 13.