A connector for display shelve comprises a round and flat first block, a corresponding second block, and a pin member. The first block includes a semicircle trough on top portion and one side thereof extending downward, a semicircle recess horizontally lying underneath the trough having a convexity at center portion which has a through hole in parallel with the recess, a semicircle groove, horizontally, lying underneath the recess, and two notches on two sides of the periphery. The second block has a semicircle trough, and a semicircle groove in corresponding to the trough and the groove of the first block both in size and location. The second block has further two convexities at respective end of center line having a through hole in each of the convexities, and a concavity located inbetween the two convexities and is corresponding to the convexity of the first block. Thus when the two blocks are connected together by means of the pin member and the grooves of the first and the second blocks have clamped the mainframe, the connector is slidable. When the connector has slid into a desired position, the supporting frames and partition frames are installed into the grooves.