The invention provides a safe drilling machine for concrete tamping in building construction. The safe drilling machine comprises a motor box, a motor output shaft in the motor box is in transmissionconnection with the tail end of a drilling rod, the motor box is of a cylinder structure, and a protective cover sleeves the outer side of the motor box in a sliding mode. When the drilling rod of thesafe drilling machine is drilling, the protective cover can block the periphery of the drilling rod; as the drilling rod penetrates into a drilling hole, the motor box slides downward relative to theprotective cover, and the protective cover is not moved to play a role in protection; when the drilling is stopped, under the elastic action of a spring, the motor box moves back to an original position; when the drilling bit of the drilling rod is subjected to a small squeezing force, a brake ball is stuck in a spring chamber; when the drilling bit of the drilling rod is subjected to a large squeezing force, the brake steel ball disengages from the spring chamber, a pressing rod slides downwards, a pressure sensor is forced to stop the rotation of a motor in the motor box to play a protective role, and the buffer spring plays a buffering role.