Underground pipeline protection device

The invention discloses an underground pipeline protection device which comprises a pair of supporting frames, the supporting frames are vertically arranged on the two sides, perpendicular to the axial direction of the underground pipeline, of the underground pipeline, and buffering sliding blocks are arranged on the inner sides of the supporting frames in a sliding mode in the vertical direction; the lower ends of the pair of connecting rod bodies are correspondingly and rotationally arranged on the pair of buffer sliding blocks, and the upper ends of the connecting rod bodies are obliquely arranged; the cambered surface plate covers the underground pipeline in a suspended mode, the upward side of the cambered surface plate is in a protruding cambered surface shape, the length of the cambered surface plate in the horizontal direction is smaller than the distance between the pair of supporting frames, the upper end of the connecting rod body is rotationally arranged at the bottom of the cambered surface plate