The invention provides a microorganism soil sanitation solar energy loop heat pipe system with a changed coiler coiling density. The microorganism soil sanitation solar energy loop heat pipe system comprises a solar device and a loop heat pipe device, the solar device comprises a solar thermal collector and a heat exchanger, the heat exchanger is connected with the solar thermal collector, air isinput into the heat exchanger through a draught fan and is heated in the heat exchanger to form hot air, and the hot air enters the loop heat pipe device; the loop heat pipe device comprises an air inlet channel, an air outlet channel, a loop heat pipe and a gas cavity, the loop heat pipe comprises an evaporation end and a condensation end, and the condensation end is arranged on the wall face ofthe lower portion of the gas cavity; the gas cavity is arranged in soil, the condensation end is coilers located on the outer wall face of the lower portion of the gas cavity, the wall face of the lower portion of the gas cavity is of a round structure, and the density of the coilers is gradually increased from the center of the round structure in the radial direction. By means of the arrangement,heat can be started to be emitted from the outer end of the round structure inwards. The pipe diameters of the coilers on the outer end are larger, so that more heat is needed for achieving overall even radiating, the soil repairing effect is strengthened, and the overall even repairing is achieved.