The invention provides a method for rapidly fixing a micro-quake sensor underground. The fixing method is characterized in that on the basis that an anchor rod (11) provided by the support way of an underground coal roadway driving working surface anchor rod (11) is taken as a carrier, the conventional buried type installation way is changed, and a sensor and the anchor rod (11) are fixedly connected integrally by rapidly fixing the micro-quake sensor device underground. The device comprises an outer cover and a connector, wherein the outer cover consists of a bottom plate (2), a cover body (3), an external sound wave insulating material (4) and closing holes (5), wherein the connector consists of a protruding shaft (7), a baffle plate (8) and a fixing bolt (9). By adopting the method, a series of problems of complex installation procedures, high time consumption, difficulty recovery and the like in the conventional micro-quake sensor installation way are solved. Rapid installation and detachment of the sensor are realized. Moreover, the cover body provided by the device can be used for fixing and protecting the sensor, and plays a role in insulating and eliminating noise.