Abstract: The present disclosure relates to the technical field of campus local area networks (LANs), and particularly discloses a method and system for implementing multi-service bearer in a passive optical LAN (POL). The method includes: step S1: constructing a POL, and accessing an entire campus network at a bandwidth of Gigabit according to a point-to-multipoint star topology including three layers: a core layer, a convergence layer, and an access layer, to form a 10 Gbit backbone, wherein an optical network terminal enters a room and is deployed according to such a manner that one classroom or functional room has one terminal mode; step S2: planning and managing the entire POL, defining a plurality of LANs through software definition (SD-LAN), wherein different LANs bear different services; and step S3: allocating different service bandwidths to different LANs through a sharding mechanism of the PON, and the like.