The invention provides a 3D printer workbench which comprises a printing platform under a 3D printer spray head and a cleaning mechanism for cleaning residues on the printing platform, wherein the cleaning mechanism and the printing platform are movably connected; the printing platform comprises a bottom plate, a thermal insulation layer, a constant temperature layer and a panel which are sequentially stacked from bottom to top; the constant temperature layer comprises a plurality of constant temperature plates which are arranged on the same horizontal plane in parallel and thermal insulation stripes arranged between every two thermal insulation plates, and each constant temperature plate is connected with a control unit which is used for controlling a temperature of the constant temperature plate. The workbench disclosed by the invention has a high residue cleaning efficiency and saves time and labor; a temperature of a contact face between a printed product and the panel is even to avoid the edge warping phenomenon, so that printing quality is improved; by controlling switches and temperatures of different constant temperature plates, energy waste caused by wholly heating the panel is avoided.