Abstract: Objective:To observe the pathological damage of the skin and tissue of the compression parts after different time of compression in rats.Methods:Sixty-five Sprague-Dawley rats were randomly divided into the six groups(8 rats each group),which included the control group(group A,without compression),group B(compression for 1 h),group C(compression for 2 h),group D(compression for 3 h),group E(compression for 4 h) and group F(compression for 6 h).The time of compression and compression interval in all groups were the same,and the whole course was 24 h.The pathological damage of the skin and tissue of compression parts were observed after compression.Results:Erythema in 1 rat of group B,2 rats of group C,5 rats of group D,8 rats of group E and 8 rats group F were found.The number of erythema in group D,E and F were significantly more than that in group A(PConclusions:The damage of the skin and tissue of compression parts is obvious after 2 h of compression,skin damage is more serians when the pressure is prolonged.