Sheep bone collagen was used as the research object to explore the effects of different ultra-high pressure on the microstructure， thermal denaturation temperature， pyridine cross linkers of collagen and the changes of collagen spatial structure. The results showed that the micromorphology of ultra-high treated collagen polymerizes temporarily at a pressure of 100-300 MPa. When the pressure exceeded 400 MPa， the collagen structure expands again. DSC results showed that the denaturation temperature of collagen after ultra-high pressure treatment decreased from 44.9 ℃ (control group) to 31.7 ℃. The contents of hydroxyl sine pyridine (HP) and lysine pyridine (LP)， the cross-linkers of collagen pyridine， were significantly decreased with the increasing of ultra-high pressure pressure and the prolonging of pressure holding time (P<0.05). HP and LP were negatively correlated with ultra-high pressure and holding time (P<0.01).