An embodiment of the invention discloses a method with a modulation mode self-adapting to the alternation. The method comprises the following procedures: selecting a probability distribution function; randomly generating a function value of a probability accumulation function corresponding with the probability distribution function, confirming an independent variable interval according to the function value, and taking the auxiliary modulation mode corresponding with the independent variable interval as a modulation mode of the alternating time of current modulation mode. The embodiment of the invention also discloses a device with a modulation mode self-adapting to the alternation. The plan of the embodiment according to the invention does not require a signal-to-interference and noise ratio which is required in prior art when the modulation mode is altered and is fed back by the receiving end, and thereby prolonging the feedback period of the SINR value and reducing the feedback quantity of the SINR value.