At present, it is necessary to measure the rail verticality and end slope by contact tools such as feeler gauge and angle gauge before welding rails in China. Due to the complicated manual measurement steps and low measurement efficiency, a non-contact rail measurement system based on laser profilometer is developed. Four laser profilers collect the information of the whole end face and side of the rail, then use the principle of dihedral angle to complete the calculation of the angle between the end face and side, end face and bottom surface of the rail. Finally, the end face slope is measured by the right-angle ruler model. After the field tests, the repeated measurement error of rail verticality is less than 0. 2°, the measurement accuracy can reach up to 0. 3°, and the limit error of end face slope reaches 0. 04 mm. The experimental results prove that the designed system can efficiently and stably complete the inspection of rail verticality and meet the actual test requirements.