Hi
I made steering wheel model, but when i used subdivision surface this happens:
there is that annoying roughness
thanks for help 
You haven’t shown your mesh but there is something wrong with it. Ideally you want your edge flow to follow the shapes of your object.
Remove any double vertices
Remove any faces that are inside the mesh
Check for non-manifold edges (look in select menu)
If you have ngons (faces with more than 4 edges) get rid of them
Yeah would need to see the mesh. Preferably .blend but a good wireframe image of the problem areas would do too.
Btw. you can take screenshots in Blender itself by pressing ctrl+F3. Probably quicker way to take screenshots of it in Windows and also leaves unnecessary parts off, including the title bar with your name in it.
and i am new in blender maybe half year blender using so can you explain little more specifically
here is blender file
Don’t know what the design is but for the looks of it, face loops don’t follow the shapes and there are n-gons (faces with more than 4 edges/vertices). I made a “generic” steering wheel shape as an example.
Left: original, subdivided.
Middle: assumed shape with proper topology
Right: same as previous but topology used to add sharp edges and more detail.
steering_wheel_topology.blend (546 KB)
hi
how i can make that there is no 4 edge faces
You probably mean more than 4. You can cut n-gon faces with vertex connect (select two of its vertices and press J [as in Join]). Could also use knife tool (K) to do that.
You’ll run into problems like n-gons with 5 vertices/edges and turning that into a quad face is not possible with just one cut. You would have to get rid of the fifth vertex or add more cuts, possibly routing more edge loops through quads to have the needed vertices to get rid of the triangle that was left.
Here’s an old introduction video that explains quite well what is going on http://www.youtube.com/watch?feature=player_detailpage&v=Vdx70AExNyg#t=101
now its better
thanks for help 