An epitaxial growth method for preventing auto-doping effect is presented. This method starts with the removal of impurities from the semiconductor substrate and the reaction chamber to be used. Then the semiconductor substrate is loaded in the cleaned reaction chamber to be pre-baked under vacuum conditions before the extraction of the dopant atoms desorbed from the surface of the semiconductor substrate. Next, under high temperature and low gas flow conditions, a first intrinsic epitaxial layer is formed on the surface of said semiconductor substrate. Following this, under low temperature and high gas flow conditions, a second epitaxial layer of required thickness is formed on the structural surface of the grown intrinsic epitaxial layer. Last, silicon wafer is unloaded after cooling. This method can prevent auto-doping effect during the epitaxial growth on semiconductor substrate and thus ensure the performance and enhance the reliability of the devices in peripheral circuit region.