The effect of curing time on the crosslinking density and properties of silicone rubber were studied,and the crosslinking density of silicone rubber at different curing time was calculated u-sing equilibrium swelling method and stress-strain method.The results showed that with the prolong of curing time,the tensile strength and elongation at break of silicone rubber showed a slight down-ward trend,while the tear strength first increased and then decreased,and the hardness remained basi-cally unchanged;The crosslinking density values were consistent with the changes in mechanical prop-erties;After hot air aging,the change rate of tensile strength and elongation at break had significantly decreased,while the change in hardness was basically consistent.