A data transmission method and a data transmission device are provided. The method includes: receiving first indication information sent by a network side device, the first indication information is used to instruct the UE to send a first signal; and determining actual first uplink transmission characteristic of the first signal when valid first uplink transmission characteristic of the first signal is not obtained, and sending the first signal through the actual first uplink transmission characteristic, or not sending the first signal when valid first uplink transmission characteristic of the first signal is not obtained.