Texture and bone animation problem

-import 3ds file
-merge 3 objects to 1 object
-vertex grouping
-apply textures to 3 objects using material
-make bone animation using armature

But the result, some of the texture information is at the incorrect position.
For example, the shirt image of the character is displayed at the character’s
left and light legs.

Help me what's the reason?

The reason is simple... SIO2 is working on a vertexgroup basis and blender work on a face basis... what you should do is this:

1. Import your model
2. Create the armature
3. Link the armature with the model and automatically create the vertexgroups
4. Link all the triangles to the appropriate vertexgroup corresponding to the bone
5. Assign the appropriate material for the vertexgroup
6. Repeat 4 and 5 for every bone and make sure that ALL triangles are attached to only ONE vertexgroup.
7. Create your bone animation and export.