how to load *.Obj Files with number of vertices more than 65535 in run-time ?

the application couldn’t load the *.obj 3d Model in runtime, then an error message appears showing that the number of vertices couldn’t exceed 65535!

how to pass the problem and what is the suggestion to load and view files with more than 65535 vertices?

Well it’s not clear how you actually load those models at runtime. Also what Unity version do you use? In the latest version they implemented 32bit index buffers which have to be activated on the mesh when creating the mesh. If you’re using an older Unity version you would need to “manually” split the model into several Meshes as you’re loading the model. So if you use an OBJ loader that only creates a single mesh out of the OBJ file you either have to find another one that actually does the splitting or you have to change the one you’re using.

Since the information how you load the file is not included in your question we can’t help any further.