ELECTRONIC UNIT ATTACHMENT STRUCTURE

PROBLEM TO BE SOLVED: To provide an electronic unit attachment structure with a simple structure.SOLUTION: A case 5 of an electronic unit 3 includes a case body 50, a first projection part 51 and a second projection part projected from one side surface 50c of the case body 50, and a lock part 52 attached to the other side surface 50d. A case 4 of an electric connection box 2 includes a vertical wall 6 which is erected orthogonally to an upper surface 40a of the case 4 and on which a first insertion part 61 and a second insertion part are formed and a lock receiving part 42. When the first projection part 51 is inserted into the first insertion part 61, the second projection part is inserted into the second insertion part, and the electronic unit 3 is rotated around the first projection part 51, the lock part 52 is engaged with the lock receiving part 42 and the electronic unit 3 is attached to the upper surface 40a. In the state, movement of the second projection part in an arrow Y direction and a Z direction is regulated by the second insertion part.