A passive optical network communication method, comprising: receiving, by an optical line terminal, OLT, an Ethernet packet, wherein the Ethernet packet carries an optical network unit identifier; looking up, by the OLT, a correspondence between the optical network unit identifier and an optical network unit type based on the optical network unit identifier, to determine whether an optical network unit that receives the Ethernet packet is a first type of optical network unit, wherein the optical network unit type comprises the first type of optical network unit and a second type of optical network unit, and a packet receiving rate of the first type of optical network unit is different from a packet receiving rate of the second type of optical network unit; when it is determined that the optical network unit is a first type of optical network unit: looking up, by the OLT, a correspondence between the optical network unit type and a channel based on the first type of optical network unit, to determine a channel corresponding to the first type of optical network unit; and encapsulating, by the OLT, the Ethernet packet into a GPON encapsulation method, GEM frame or a XGPON encapsulation method, XGEM frame, and sending the frame to the first type of optical network unit by using the determined channel; characterized in that the determine a channel corresponding to the first type of optical network unit comprises: determine, by the OLT, a first channel or a second channel corresponding to the first type of optical network unit; wherein the encapsulating the Ethernet packet into a GEM frame or a XGEM frame comprises: mapping, to a low bit of an output level, a bit output by the first channel, and mapping, to a high bit of an output level, a bit output by the second channel. receiving, by an optical line terminal, OLT, an Ethernet packet, wherein the Ethernet packet carries an optical network unit identifier; looking up, by the OLT, a correspondence between the optical network unit identifier and an optical network unit type based on the optical network unit identifier, to determine whether an optical network unit that receives the Ethernet packet is a first type of optical network unit, wherein the optical network unit type comprises the first type of optical network unit and a second type of optical network unit, and a packet receiving rate of the first type of optical network unit is different from a packet receiving rate of the second type of optical network unit; when it is determined that the optical network unit is a first type of optical network unit: looking up, by the OLT, a correspondence between the optical network unit type and a channel based on the first type of optical network unit, to determine a channel corresponding to the first type of optical network unit; and encapsulating, by the OLT, the Ethernet packet into a GPON encapsulation method, GEM frame or a XGPON encapsulation method, XGEM frame, and sending the frame to the first type of optical network unit by using the determined channel; characterized in that the determine a channel corresponding to the first type of optical network unit comprises: determine, by the OLT, a first channel or a second channel corresponding to the first type of optical network unit; wherein the encapsulating the Ethernet packet into a GEM frame or a XGEM frame comprises: mapping, to a low bit of an output level, a bit output by the first channel, and mapping, to a high bit of an output level, a bit output by the second channel.