To provide a board mounting structure which can lessen a mounting body in size keeping a wiring space large for a lead wire and where a connector can be easily fitted.

A board mounting structure which mounts a board 1 on a mounting body 3 is composed of board terminals 5 provided upright on the board 1, terminal insertion slits 13 which are provided on the mounting body 3 and where the board terminals 5 are inserted, engaging parts 7 and 13a which are provided on the board terminals 5 and the terminal insertion slits 13 so as to control the movement of the board terminals 5 engaging with each other in such a state that the board terminals 5 are made to slide in the direction of Y intersecting to the insertion direction of X, so that the board 5 can be mounted on the mounting body 3 through the intermediary of the board terminals 5 without using additional parts. Therefore, the board mounting structure of this constitution is capable of decreasing in mounting space and lessening the mounting body 3 in size keeping a wiring space large for a lead wire, moreover the insertion force of a connector 17 is absorbed by the mounting body 3, so that the board 1 can be kept stable in a mounting state even if the connector 17 is inserted by a large force.