Disclosed are a data transmission method and a related product. The method includes: when it is detected that a data replication transmission function of a PDCP layer entity is activated, a terminal enabling a first RLC layer entity, a second RLC layer entity being in an enabled status; and invoking the PDCP layer entity to determine a first PDCP PDU associated with a first PDCP SDU, and sending the first PDCP PDU to the first RLC layer entity, wherein the first PDCP PDU is used for the first RLC layer entity and a MAC layer entity to process the first PDCP PDU into a MAC PDU and send same.