This application discloses a packet forwarding method and apparatus, a system, a device, and a storage medium. The method is applied to an in-vehicle network and includes: obtaining, by a network device, a plurality of packets carried on an Ethernet link in the in-vehicle network, where the plurality of packets are packets of one or more application categories; determining a traffic class of each packet based on an application category of each packet in the plurality of packets; adding each packet to a forwarding queue corresponding to the traffic class based on the traffic class of each packet; and scheduling and forwarding packets in all forwarding queues based on an absolute priority and a traffic class corresponding to each forwarding queue, and using a shaper in a forwarding queue of at least one traffic class in intermediate traffic classes in the scheduling and forwarding process. For the plurality of packets carried on the Ethernet link, a transmission requirement of the packets is met, so that the scheduling and forwarding have better performance. Therefore, the method is applicable to an Ethernet-based in-vehicle network architecture. The use of the shaper ensures a bounded latency.