Developing visual pretreatment and result extraction system of three dimensional finite element simulation for titanium alloy laser rapid prototyping，after it further studies of birth-death element and command stream. It simplified the numerical simulation modeling process，thus who do not understand MSC.MARC operation can facilitate the simulation analysis and results extraction of rapid prototyping. This system mainly has five parts：it established the geometry finite element to the workpiece and base plate in accordance with the provisions，material properties，light setup，and post-processing. Through the corresponding input parameters can get MSC.MARC command stream，and run the file can make rapid prototyping process simulation. It made the simulation of titanium alloy laser rapid prototyping easier，and more sets of parameters can be easily made contrast simulation. It by using two groups of parameters utilizes the system for example calculation，and get satisfied results.