A frame aggregation method, wherein the method is applied to a wireless smart ubiquitous network, Wi-SUN, field area network, FAN, the Wi-SUN FAN comprises a first forwarding node device, a first node device, and a second node device, and the method comprises: receiving, by the first forwarding node device, a first data frame sent by the first node device and a second data frame sent by the second node device, wherein the first data frame comprises a first media access control, MAC, header and a first MAC service data unit, MSDU, and the second data frame comprises a second MAC header and a second MSDU; determining, by the first forwarding node device, that a destination MAC address in the first MAC header is the same as a destination MAC address in the second MAC header, and generating, by the first forwarding node device, a first aggregated frame based on the first data frame and the second data frame, wherein the first aggregated frame comprises a first aggregated MAC header and a first aggregated MSDU, a destination MAC address in the first aggregated MAC header is the same as the destination MAC address in the first MAC header or the destination MAC address in the second MAC header, the first aggregated MSDU comprises a first sub-MSDU and a second sub-MSDU, the first sub-MSDU comprises the first MSDU and a source MAC address in the first MAC header, and the second sub-MSDU comprises the second MSDU and a source MAC address in the second MAC header; and sending, by the first forwarding node device, the first aggregated frame to a second forwarding node device, wherein the first forwarding node device is a cluster head forwarding node device, and the method further comprises: receiving, by the first forwarding node device, a network setting frame from a border router, wherein the network setting frame is used to indicate a time at which the first forwarding node device reports the first aggregated frame and a time at which each of the first node device and the second node device collects data; and determining, by the first forwarding node device based on the network setting frame, a deadline for reporting the first aggregated frame; and the sending, by the first forwarding node device, the first aggregated frame to a second forwarding node device comprises: sending, by the first forwarding node device, the first aggregated frame to the second forwarding node device based on the deadline. receiving, by the first forwarding node device, a first data frame sent by the first node device and a second data frame sent by the second node device, wherein the first data frame comprises a first media access control, MAC, header and a first MAC service data unit, MSDU, and the second data frame comprises a second MAC header and a second MSDU; determining, by the first forwarding node device, that a destination MAC address in the first MAC header is the same as a destination MAC address in the second MAC header, and generating, by the first forwarding node device, a first aggregated frame based on the first data frame and the second data frame, wherein the first aggregated frame comprises a first aggregated MAC header and a first aggregated MSDU, a destination MAC address in the first aggregated MAC header is the same as the destination MAC address in the first MAC header or the destination MAC address in the second MAC header, the first aggregated MSDU comprises a first sub-MSDU and a second sub-MSDU, the first sub-MSDU comprises the first MSDU and a source MAC address in the first MAC header, and the second sub-MSDU comprises the second MSDU and a source MAC address in the second MAC header; and sending, by the first forwarding node device, the first aggregated frame to a second forwarding node device, wherein the first forwarding node device is a cluster head forwarding node device, and the method further comprises: receiving, by the first forwarding node device, a network setting frame from a border router, wherein the network setting frame is used to indicate a time at which the first forwarding node device reports the first aggregated frame and a time at which each of the first node device and the second node device collects data; and determining, by the first forwarding node device based on the network setting frame, a deadline for reporting the first aggregated frame; and the sending, by the first forwarding node device, the first aggregated frame to a second forwarding node device comprises: sending, by the first forwarding node device, the first aggregated frame to the second forwarding node device based on the deadline. receiving, by the first forwarding node device, a network setting frame from a border router, wherein the network setting frame is used to indicate a time at which the first forwarding node device reports the first aggregated frame and a time at which each of the first node device and the second node device collects data; and determining, by the first forwarding node device based on the network setting frame, a deadline for reporting the first aggregated frame; and the sending, by the first forwarding node device, the first aggregated frame to a second forwarding node device comprises: sending, by the first forwarding node device, the first aggregated frame to the second forwarding node device based on the deadline.