The invention provides a method for monitoring the pile foundation quality in the construction process. The method includes the steps that at a trial pile-forming stage, trial pile-forming tamping iscarried out according to preset tamping parameters, and the correlational relationship between frequency spectrum features of elastic waves generated during trial pile-forming tamping and quality parameters for reflecting the construction quality is determined; and at a formal construction stage, formal construction tamping is carried out according to the preset tamping parameters, real-time frequency spectrum features of the elastic waves generated during formal construction tamping are determined, real-time quality parameters are calculated according to the real-time frequency spectrum features and the correlational relationship, and the current construction process is subjected to quality monitoring. A test pile is tamped through the preset tamping parameters, and the correlational relationship between the frequency spectrum features of the elastic waves and the quality parameters is obtained; and at the formal construction stage, the quality parameters are calculated according to the correlational relationship, and bearing force is monitored.