Terrestrial magnetism detector

The invention discloses a terrestrial magnetism detector. The terrestrial magnetism detector comprises a roadbed body, wherein a road groove is formed in the top of the roadbed body; the road groove is internally provided with a terrestrial magnetism detector body; a cover body is installed on the top of the terrestrial magnetism detector body; a bolt is installed on the top of the cover body through a thread; a sliding sleeve body sleeves the outer side of the terrestrial magnetism detector body; two sides of the bottom of the sliding sleeve plate are welded with clamping heads respectively;the bottom of each clamping head is in cup joint with a first telescopic spring; and the inner wall of the road grove is welded with a sleeve. According to the terrestrial magnetism detector, by setting a telescopic damping mechanism, when a vehicle runs over the detector, after the detector is subjected to pressure, the detector can be automatically shrunk into the road groove, so that rolling compaction with greater dam