The invention discloses a silane modified polymer. The structural formula of the silane modified polymer is shown in the description, wherein n is equal to 1-5000, m is equal to 2-5000, x is equal to 1-10, w is equal to 1-10, R1 is one of groups shown in the description, and R is a group containing silicon methoxyl or silicon ethyoxyl. The silane modified polymer is prepared from raw materials through polymerization in parts by weight as follows: 100 parts of polyalcohol, 1-100 parts of isocyanate, 1-10 parts of cyclosiloxane and 1-30 parts of alkoxy silane. The silane modified polymer has good cross-linking and curing capacity and has excellent tensile strength and hardness after curing.