The invention discloses a data transmission optimization method based on linear network coding. The method comprises the steps that 1, data information needing to be transmitted is grouped in a sending source, and the grouped data is coded through a linear network coding technique; 2, the grouped data is forwarded to a relay vehicle to be subjected to a recoding operation and forwarded; 3, if a next-hop vehicle is not a destination vehicle, the step 2 is repeated; 4, when the destination vehicle receives the data, linear correlation calculation is firstly conducted, and if the data does not have the linear correlation, the data is received; 5, a decoding operation is conducted on the received data to obtain original data through recovery, and if decoding cannot be conducted, the condition is fed back to the last-hop vehicle; and 6, if the destination vehicle cannot obtain the original data through decoding, the condition continues to be fed back to the last-hop relay vehicle until the original data is obtained through decoding. According to the method, the packet loss rate generated in the data transmission process can be effectively decreased, and the data retransmission times are decreased.