A coupling member (1) includes a pair of support members (11a, 11b) that are linked at one end so that an opening is formed at the opposite end, and the back sides thereof are situated opposite to each other, and a pair of engagement holes (12a, 12b) that are respectively formed in the support members (11a, 11b) in the thickness direction so as to extend from the back sides, and are situated opposite to each other, the outer side (a to d) of each of the support members (11a, 11b) forming a tapered surface that gradually slopes outward in the downward direction. An assembly shelf utilizes the coupling member (1). The assembly shelf utilizes an L-shaped angle, and is configured so that a shelf board member is not provided with a protrusion, a tool is unnecessary during assembly, and a middle shelf board can be removed conditionally.