Aiming at the problem of complex structure and low efficiency of robot language interpreter, a modularization method for interpreter was proposed. The interpreter was divided into three modules: error checking, precompiling and compiling. The interpreter main function was parsing the teaching files and generating the intermediate code. In the controller system, the motion planner obtained the intermediate code for motion planning, and then controlled the correct motion of the robot. The interpreter was realized by C++ programming. Finally, taking the 6-DOF industrial robot as the research object, the functions of the interpreter were verified. The generated trajectory can meet the needs of industrial production.