An improved laser triangulation probe was designed based on the traditional direct laser triangulation method. A new single lens design was proposed based on general direct laser triangulation ranging method. The optical path was improved. In optical systems, a beam splitter was used to replace the focusing lens and imaging lens of traditional laser triangular probe, making it coaxial with concentrator lens and photo detector, which made the system structure more compact, and the Scheimpflug condition was deduced to meet the structure. While taking advantage of Zemax optical design software to simulate the optical system, pupil diameter of 4 mm, focal length of 20 mm, total length of 20.5 mm, can achieve miniaturization of measuring system. Together with the appropriate light source and detector, a larger scope of work can be obtained in ensuring high measurement accuracy of the premise, and improving the environmental adaptability of measurement system. It can be widely used in industrial real time online testing and military fields.