I have 2 mesh and i have join them with ctrl+j and made a single mesh. And i want the pivot point to be center of the new mesh i have made from joining the 2. I have tried geometry to origin but also it did not fix the center. Its on the top of the match stick and not in the center of my mesh. I can go in the edit mode and move my model and set the pivot manually. But without doing manually how can to fix it to the center.
I think i got my solution hope it helps for others. Select you object in object mode. Then, simply Press CTRL+ALT+SHIFT+C and when the menu pops up just press O as every body suggested but the center point never come in the center. After following all above step. After u press CTRL+ALT+SHIFT+C popup and we select origin to geometry still to it do not come at center. Go to left hand panel as show in .gif image . Set origin (or u can press f6 operator popup) there is type (origin to geometry) and below it is center in that there are 2 option (median center and bound center) if u click on the median center as default is on the top only and if we select and change to bound center it come exactly to the center of all the geometry. That's what i need i got. Thanks to everybody who have taking the efforts.