In the mobile communication system according to an embodiment of the invention provides a method and apparatus for a terminal to adjust the TX rate. The method of the present invention, the buffer is empty (empty) state whether or when the buffer is not (non-empty) state that the judgment process, and not the buffer is empty, which are empty (non-empty) status work reported in the last buffer size for the total transmission of the process of buffers compared with the threshold value set in the ratio of the size and the process, and the set indication information according to the comparison result, setting the indication information indicating that you are happy with the TX rate to the base station it involves. LTE (Long Term Evolution), MAC PDU (Medium Access Control Protocol Data Unit), a happy bit (Happy bit)