A pile driver for civil engineering comprises two stand columns, wherein a sliding sleeve is mounted on each stand column in a matched manner and can move up and down along the stand column; a fixing frame is mounted between the sliding sleeves; a drill is arranged in the middle of the fixing frame; vertical sliding grooves are formed in two sides of the drill; guiding blocks are arranged on inner sides in the middle of the fixing frame and are located in the sliding grooves; an output shaft of the drill faces downwards; a matching block is mounted on the output shaft of the drill; two circular sliding rails are arranged in the fixing frame; a circular sliding ring is arranged between the circular sliding rails in a matched manner and can rotate along the circular sliding rails; a plurality of mounting holes are evenly formed in the circular sliding ring; and a bearing block is arranged in each mounting hole, and the outer circle of the bearing block is fixedly matched with the mounting hole. Piles are driven by the drill to rotate, meanwhile, the sliding sleeves are driven by hydraulic cylinders to move downwards, and the piles are driven on the ground in a rotating manner. For pile holes with different diameter requirements, the corresponding piles can be adjusted by rotating the circular sliding ring, the time for replacement of the piles is shortened, and the construction efficiency is effectively improved.