A control method and a control device of an engine are introduced. During the process of the engine controlling, the control unit does the adaptive learning for the actual target value of the feedback of different aims, and following the dynamic spectrogram generation strategy optimizing compares the adaptively learning parameter of the same working status and the same time with the basic spectrogram parameter. If the compared result doesn't meet the condition, then keep the basic spectrogram parameter. And if it meets the condition, then the engine generates the dynamic spectrogram parameter. Based on the dynamic spectrogram combination strategy, the engine combines the basic spectrogram parameter and the dynamic spectrogram parameter generated to the combined spectrogram parameter instead of the basic spectrogram parameter.