The invention provides a reciprocating load adjustable concrete member hydraulic fracture testing machine. The reciprocating load adjustable concrete member hydraulic fracture testing machine comprises a power transmission frame, an anticlockwise transmission gear, an indirect gear, a clockwise transmission gear, a one-way bearing, a crankshaft, a transmission link, a guide rail, an axial force sensor, an actuation connecting rod, a convex type loading frame, a concave type loading frame, a bearing, a force transferring steel shaft, a high pressure sealed cylinder, a sealed cylinder connecting rod, a non-contact type flash ranging window, an exhaust vent and a water filling pipe, wherein the power transmission frame drives the anticlockwise transmission gear and the clockwise transmission gear to rotate in sequence, further the convex type loading frame and the concave type loading frame move up and down alternatively, and reciprocated load loading can be achieved; the one-way bearing can rotate to change direction freely, and can be used for adjusting different tooth number meshed regions of gears, so as to adjust different repeated loadings. The testing machine provided by the invention is multifunctional, the process is safe and controllable, the operation is simple and convenient, the structure is simple, and the testing machine can be used for researching the problem of hydraulic fracture of concrete members under high water pressure and reciprocating loading effects.