A method for media stream transmission, comprising: receiving, by a dynamic adaptive streaming over Hypertext Transfer Protocol DASH proxy, a segment request message that is sent by a DASH client of user equipment UE and that is used to request segment content of media; determining, by the DASH proxy, according to the segment request message, to send the segment content to the UE in a multicast mode; sending, by the DASH proxy, a multicast request message to a broadcast multicast service center BM-SC, so that the BM-SC multicasts the segment content to a multimedia broadcast multicast service MBMS client according to the multicast request message, and the MBMS client sends the segment content to the DASH client; receiving multicast transmission information, sent by the BM-SC according to the multicast request message, of the segment content, wherein the multicast transmission information comprises at least one of the following information: information about a frequency band occupied by multicast of the segment content, a service identifier of the multicast segment content, an MBMS session identifier of the multicast segment content, a transport identifier of the multicast segment content, a transport session identifier of the multicast segment content, a service area in which the segment content is multicast, and scheduling information of the multicast segment content; and sending a segment multicast instruction message to the DASH client, wherein the segment multicast instruction message carries the multicast transmission information, and the segment multicast instruction message is used to instruct the DASH client to receive the segment content by using the MBMS client. receiving, by a dynamic adaptive streaming over Hypertext Transfer Protocol DASH proxy, a segment request message that is sent by a DASH client of user equipment UE and that is used to request segment content of media; determining, by the DASH proxy, according to the segment request message, to send the segment content to the UE in a multicast mode; sending, by the DASH proxy, a multicast request message to a broadcast multicast service center BM-SC, so that the BM-SC multicasts the segment content to a multimedia broadcast multicast service MBMS client according to the multicast request message, and the MBMS client sends the segment content to the DASH client; receiving multicast transmission information, sent by the BM-SC according to the multicast request message, of the segment content, wherein the multicast transmission information comprises at least one of the following information: information about a frequency band occupied by multicast of the segment content, a service identifier of the multicast segment content, an MBMS session identifier of the multicast segment content, a transport identifier of the multicast segment content, a transport session identifier of the multicast segment content, a service area in which the segment content is multicast, and scheduling information of the multicast segment content; and sending a segment multicast instruction message to the DASH client, wherein the segment multicast instruction message carries the multicast transmission information, and the segment multicast instruction message is used to instruct the DASH client to receive the segment content by using the MBMS client.