The invention relates to a method for detecting, controlling and automatically compensating pressure in a polishing process, including: detecting a pressure between a polishing wheel and a polished workpiece by a detection shaft or a moment generated on the detection shaft, and outputting the detected pressure or moment to a controller; comparing the detected pressure or moment with a preset pressure or moment and determining whether there is a difference between them; calculating a compensation feeding amount based on the difference and outputting an adjustment signal to an adjustment shaft based on the compensation feeding amount; and moving the adjustment shaft correspondingly based on the adjustment signal so as to drive the polishing wheel or the polished workpiece to move correspondingly to adjust a relative position between the polishing wheel and the polished workpiece so that the difference keeps consistent.