The present invention discloses a method of data retransmission in coordination service transmission and access network gateway thereof. Wherein, the method includes: in coordination service transmission, access network gateway receives the service data requested by the coordination terminal, caches the data and transmits it to the corresponding destination terminal; the access network gateway executes retransmission strategy, and when decides data retransmission is needed, retransmits the cached data to the corresponding destination terminal. The access network gateway is used to receive the service data requested by the coordination terminal, to cache the data and transmit it to the corresponding destination terminal, to retransmit the cached data to the corresponding destination terminal when data retransmission is needed. Using the present invention, to the problem of service data retransmission in coordination service transmission, the service data transmission efficiency is effectively improved.