In present work, in order to obtain the quantitative regularity the effects of molecular weight of methyl-vinyl silicone rubber (MVSR) on the values of various crosslinking parameters have been investigated with the theory of radiation crosslinking. From obtained experimental results, it can be found that the straight linear relationship exits between the weight average molecular weight and the parameters, such as gelation dose (R,g,) , total degree of cross-linking per unit dose (q,0,), total degree of degradation per unit dose (α,0,) , degree of cross-linkling in sol per unit dose (q,0(s) ,) , degree of degradation in sol per unit dose(α,0(s) ,degree of cross-linking in gel per unit dose (q,0(g) ,) , degree of degradation in gel per unit dose(α,0(g) ,) , total cross-linking index (γ) , cross-linking index in sol (γ,(s) ,) , cross-linking index in gel(γ,(g) ,) ,α,0,/q,0, α,0(s) ,/q,0(s) , α,0(g) ,/q,0(g) , and G,seiss, Value, but the G,cross, Value is proportional to reciprocal of the weight average molecularweight, we get,http://html.publish.founderss.cn/rc-pub/api/common/picture?pictureId=42648422&type=,http://html.publish.founderss.cn/rc-pub/api/common/picture?pictureId=42648424&type=,http://html.publish.founderss.cn/rc-pub/api/common/picture?pictureId=42648423&type=,It is seen that the higher the initial molecular weight of MVSR, the faster the rate of cross-linking is. There is converse effect for polyether acrylic isocyanate and the like, but the straight linear relationship between molecular weight of oligomer and the value of various cross-linking parameters still exists.,In this paper, the effect of different isocyanate structure on the activity of the terminal acrylic group of oligomer was also investigated and the activity order is as follows:,polyether acrylic hexa-methylene isocyanate > polyether acrylic toluene isocyanate > polyether acrylic 4,4'-diphenyl methylene isocyanate.