A hydraulic drive system for an operating table, the system comprising an oil supplying device for providing hydraulic oil, an oil returning device and an oil returning circuit assembly; the oil returning circuit assembly comprises two oil cylinders (261, 262), two reversing valve assemblies and two two-way hydraulic locks; a rodless cavity (2611, 2621) of each oil cylinder is connected to a working interface of the reversing valve assembly via a first oil path (31), and a rod cavity (2612, 2622) of each oil cylinder is connected to another working interface of the reversing valve assembly via a second oil path (32); an oil returning opening of each reversing valve assembly is connected to the oil returning device via an oil returning path (30); the oil returning path (30) is provided with an on-off control valve thereon; and the first oil path (31) and the second oil path (32) are subjected to two-w control via the two-way hydraulic lock. The system enables piston rods of the two oil cylinders (261, 262) to move independently and to move synchronously, thus simplifying a system structure, providing reliability and reducing cost.