To provide a system desk in which leg panels and a back panel are integrated, and which has fewer components, and a changeable layout.

Four rectangular standing panels 12 to 15 for supporting a top 11 are adopted. Out of the four standing panels, two standing panels 12 and 13 are long standing panels, whereas the two standing panels 14 and 15 are short standing panels. On each of standing panels, many assembly small holes 18 arranged at regular intervals in two rows so that the holes reach from a upper side to a lower side in the vertical direction to be a longitudinal direction are formed. The top panel is horizontally supported by the total eight assembly holes at the same height from the lower side of the four standing panels.