A packet processing method includes: a first device receives a packet from a second device; the first device determines a first queue buffer used to store the packet, and determines a first upper limit value of the first queue buffer based on an available value of a first port buffer and an available value of a global buffer, where the global buffer includes at least one port buffer, the first port buffer is one of the at least one port buffer, the first port buffer includes at least one queue buffer, and the first queue buffer is one of the at least one queue buffer. The first device processes the packet based on the first upper limit value of the first queue buffer, an occupation value of the first queue buffer, and a size of the packet.