The present invention discloses an uplink data transmission method and device. The method includes: receiving, by a network device, a control symbol sent by a terminal device by using a control time-frequency resource, where the control symbol carries control information, the control information is used to indicate a data encoding scheme used by the terminal device, the control time-frequency resource belongs to a transmission resource including a data time-frequency resource, and the control time-frequency resource and the data time-frequency resource are different; performing demodulation and decoding processing on the control symbol to obtain the control information; and performing, according to the control information, decoding processing on a data symbol sent by the terminal device by using the data time-frequency resource, to obtain uplink data.