A data transmission method and a communication apparatus. The method includes: receiving first information, where the first information indicates to delay delivering a first data packet to a first protocol layer, the first information is information at a second protocol layer, and the first protocol layer is an upper protocol layer of the second protocol layer; and delaying, based on the first information, delivering the first data packet to the first protocol layer for first duration. Therefore, data transmission efficiency can be improved, and network congestion can be relieved.