The invention discloses a geological detection device for a frozen earth area. The geological detection device comprises a micro motor, a supporting table, a screw rod, test boxes, a pressure detection head and a power source. Both the micro motor and the power source are arranged in the supporting table. An output shaft of the micro motor is connected with the screw rod through a bearing. The screw rod is provided with screw blades. Each test box is arranged between the two corresponding adjacent screw blades. A temperature and humidity sensor and a pH value detector are arranged in each test box. The tail end of the screw rod is arranged as a sharp end. The outer side of the sharp end is sleeved with the pressure detection head. A pressure sensor is arranged between the pressure detection head and the sharp end. The humidity and temperature sensors, the pH value detectors and the pressure sensor are connected with a power source respectively. According to the detection device, due to the fact that the pressure sensor is arranged between the pressure detection head and the sharp end of the screw rod, the hardness of frozen earth can be detected through the different deformation degrees of the pressure detection head when the detection device is put down into the frozen earth, and the sensors can be effectively prevented from being damaged in the using process due to the arrangement of the test boxes.