The present invention provides an uplink data sending method and a user equipment. The method includes: distinguishing uplink data to be sent, and obtaining acknowledgement data of downlink TCP service data and uplink TCP service data; buffering the acknowledgement data of the downlink TCP service data in a first buffer, and buffering the uplink TCP service data in a second buffer; and sending in priority the acknowledgement data of the downlink TCP service data in the first buffer. In embodiments of the present invention, a peak rate of a downlink TCP service may still be ensured when services are concurrent.