The invention relates to a novel low speed high torque hydraulic motor with a non-circular planetary gear train, which has the double-end flow distribution function of simultaneously transferring high pressure oil from two working ends of a front body (15) and a rear body (17) to a closed working cavity (13) in the hydraulic motor and outputting low pressure oil from the closed working cavity (13) and changes the situation where a triangular gear (3) and a planetary gear (10) receive bigger pressure from a single direction in the axial direction, so as to ensure that a triangular gear (30) and a planetary gear (29) receive balanced force in the axial direction, effectively maintain the mechanical clearance and the dynamic creation of oil films and avoid early seizure and damage under highpressure. Meanwhile, the motor also removes a collector ring (6) and a shunt ring (8), adopts a novel flow distributor (24), and selects Austempered Ductile Iron (ADI) materials and bimetal three-layer composite materials to manufacture key parts. The triangular gear (30) and a motor shaft (11) are connected by a steel ball so that the non-circular motor is characterized by high pressure, small volume, light weight, low cost and high reliability.