An auxiliary operating platform for a hospital bed comprises a supporting plate. The ends of the supporting plate are connected with vertical rods of triangular supporting frames. The lower-middle part of each vertical rod is connected with one end of a corresponding slanting rod, the other end of the slanting rod is connected with the supporting plate, and a fixing mechanism is arranged at the bottom of each vertical rod. Each fixing mechanism comprises a clamping part with a U-type neck and a connecting part of a multi-bend structure, wherein the connecting part is detachably connected with the bottom of the vertical rod. By means of the structure, the auxiliary operating platform is clamped on the vertical rods through the fixing mechanisms, an operating tray can be placed on the supporting plate stably and conveniently, and medical workers can work conveniently.