The train running on the track test line without derailment is the basic premise of track engineering scientific research test. In order to carry out the assessment of the derailment safety of the rail transportation comprehensive test line of Tongji University,this article measures the wheel-rail force of the rail transportation comprehensive test line,including wheel rail lateral force and vertical force,and then calculates the derailment coefficient and wheel load reduction rate through the wheel rail force. Results show,when the train passes at the speed of 20,30and 40 km/h,the average value of the wheel rail vertical force of the south rail is in the range of 54.91~56.14 kN,those of the north rail is in the range of 72.91~76.62 kN;t of the south rail is in the range of 5.77~7.86 kN,those of the north rail is in the range of 6.48~7.11 kN;The derailment coefficient are 0.096,0.104 and 0.113,wheel load reduction rate are 0.141,0.152 and 0.154. The derailment coefficient and wheel load reduction rate is less than the limit value,and has great safety margin,the scientific research test rail transportation line meets the requirements completely in the derailment safety evaluation.