A self-adaptive control method of a heavy-duty vehicle AMT synchronizer comprises the following steps that firstly, the synchronizer moves from an idling position to a synchronization point, a gear shifting executing mechanism electromagnetic valve is kept full open and continuously kept for a preset time t2, and a gearbox gear shifting executing mechanism rapidly reaches the synchronization point; secondly, rotation speed synchronization is conducted, by means of PWM control of the gearbox executing mechanism electromagnetic valve, it is guaranteed that a front mesh gear and a back mesh gearreach synchronization, and the synchronous state of the synchronizer is calculated and judged; thirdly, the synchronizer moves from the synchronization point to the gear engaging position, the gear shifting executing mechanism electromagnetic valve is fully open, a gearbox gear shifting executing mechanism is made to enter the gear engaged position, and when gear engaging is up to end, through real-time judgment of the speed of shifting fork displacement change, a softstop function is selected. By the adoption of the self-adaptive control method of the heavy-duty vehicle AMT synchronizer, thesynchronizer can be accurately controlled to reach a synchronization point, insufficient synchronous displacement and excessive synchronous displacement are avoided, the output synchronizing force iscorrected in real time, and accurate control over the rotation speed synchronization of the synchronizer is achieved.