The invention relates to a geological section measuring device and a measuring method. The measuring device comprises a lifting mechanism, a supporting mechanism and a measuring mechanism, the liftingmechanism comprises a horizontal base plate; two first motors are arranged on the base plate in parallel, a first lead screw is fixedly connected with an output shaft of each first motor, a ball nutis arranged on each first lead screw in a sleeved manner, the supporting mechanism comprises a supporting plate, the supporting plate is fixedly arranged between two ball nuts, three leveling devicesare fixedly arranged on the supporting plate, a horizontal plate is connected at the upper ends of the three leveling devices, the measuring mechanism is fixedly arranged on a second motor on the horizontal plate, an output shaft of the second motor is fixedly connected with a second lead screw, a base is arranged on the second lead screw in a sleeved manner, and a measuring probe is fixedly connected on the base. According to the geological section measuring device and the measuring method, the horizontal plate for supporting the measuring mechanism can be leveled, accuracy of a measuring process can be ensured, and the influence of measuring position geographies is avoided.