The utility model belongs to the technical field of oil gas field exploration and development, and particularly provides a fracturing fluid performance on-line detection system. The fracturing fluid performance on-line detection system comprises a liquid inlet of a fracturing blender truck suck-in pipe manifold end (2), wherein the liquid inlet is connected with a straight through valve (3) provided with a sensing probe interface, the other end opening of the straight through valve (3) is connected with one end of a low-pressure pipeline (4), the other end of the low-pressure pipeline (4) is connected with a mixing truck suck-in end (6) or a liquid storage tank discharge end (7), the sensing probe interface is connected with a viscosity sensing probe (9), an acidity and alkalinity sensing probe (10) and a density sensing probe (11), each sensing probe is electrically connected with a signal collector (5), and the signal collector (5) is in wireless connection with a remote receiving device (1) arranged on an instrument vehicle (8). The fracturing fluid performance on-line detection system has the advantages that the fracturing fluid viscosity measuring precision can be improved, meanwhile, the measurement of the PH value and the density value of the fracturing fluid is added, in addition, the measuring data collecting and transmission functions are also realized, and construction personnel can conveniently master the performance of fracturing fluid.