Abstract: This paper introduces the stripline beam position monitor system we designed for the linac to ring beam transport(LRBT) of China Spallation Neutron Source(CSNS). The system's physical design and parameter optimization of monitor are done based on stripline type, mechanical calibration is done to reduce error caused by machining, and the electronic system is using a commercial data processing system. The system gives effective position data in actual accelerator running, and an analysis of online measurement data is done with SVD method. According to the analysis result, accuracy of beam orbit measurement has reached the intended design goal and can meet physical tuning needs.