A hydraulic jack capable of displaying load and overload warning, belonging to the technical field of hydraulic lifting equipment. It comprises: a base, a lifting arm, a pump body, a handle, and a tray, wherein, a signal collection assembly designed to sense the load on the tray is arranged at the end of the lifting arm, and the signal collection assembly is electrically connected to a weighing controller arranged on either the base or the pump body, and the tray is arranged on the signal collection assembly. Since a signal collection assembly designed to sense the load on the tray is arranged at the end of the lifting arm and electrically connected to the weighing controller, the load sensing method by the aid of communication with the oil circuit in the prior art is abandoned and the leakage of hydraulic oil can be avoided; since the signal collection assembly is arranged at the end of the lifting arm, the entire assembly can be easily processed, installed, and maintained.