The invention discloses an information transmission method and device. The method comprises the steps that the MAC layer protocol data unit PDU transmitted by a media access control MAC layer is received, and the included wireless link control protocol RLC PDU is extracted by the MAC layer PDU; when the number of the RLC PDU is greater than 1, the serial number of each RLC PDU is acquired, and thesort order of each RLC PDU is determined based on the serial number; and the data packet included in each RLC PDU is transmitted to the PDCP layer based on the sort order.