The hydrosilylation is one of the most important methods for the synthesis of organosilicon compounds. Karstedt's catalyst [Ptn(H2C=CHSiMe2OSiMe2CH=CH2)m] is a kind of platinum catalyst which is widely used in the hydrosilylation. In this paper, we studied the catalytic activity of Karstedt's catalyst for the hydrogenation of olefins and especially aminated alkenes with trimethoxysilane and triethoxysilane