To provide an instrument box which is made easy to carry and construct by dividing the box body, can be fitted with equipment at a position matching a construction place and the equipment shape, and can decrease the number of components.

This instrument box 1 has its box by formed by standing a main-body fixed piece 10 in the inward direction of a main body 8 along both right and left end edge of the main body 8, standing a side-plate fixed piece 12 on the end edge of a part 11 bent to the whole circumference of a side plate 9 opposite the main-body fixed piece 10, and fixing the main-body fixed piece 10 and flank fixed piece 12 by clamping screws, and a support member for fitting the equipment to the main-body fixed piece 10 and side-plate fixed piece 12 has plural fitting holes 15 bored so that the fitting position can be changed vertically and is arranged between the left and right fixed pieces 10 and 12 and fixed by clamping fitting screws into the fitting holes 15.