The utility model discloses a heat exchanger with three groups of U-shaped ground buried pipes. The heat exchanger comprises inlet and outlet water collecting and dividing pipes, a ground buried pipe well hole or a filling pile and a heat exchange pipe, wherein the heat exchange pipe comprises three groups of U-shaped pipes vertically buried in the ground buried pipe well hole or the filling pile, one ends of the first group of U-shaped pipes are connected with the inlet water collecting and dividing pipes, the second group of U-shaped pipes and the third group of U-shaped pipes are connected in parallel and then form a parallel connection double-U-pipe group, two ends of the parallel connection double-U-pipe group are respectively connected with the other ends of the first group of U-shaped pipes and the outlet water collecting and dividing pipes. The heat exchanger with the three groups of U-shaped ground buried pipes has the characteristics that the heat exchange effect in the unit well hole length is good, the cost is lower, the construction and the installation are simple and convenient and are easy to implement, the ground buried well hole use ground is saved, and the applicability is wider.