Abstract: Up to the present，farmland clay is widely used to prepare lightweight ceramsite，and the technology of preparing lightweight ceramsite by using red clay as the main raw material has not yet been reported.In view of the high pileup of stripped red clay which was produced during mining process in a metallurgical flux mine，the preparation experiments of lightweight ceramsite were carried out by using red clay as the main raw material and ordinary clay，compound L，limestone，pulverized coal as additives，and the effect on lightweight ceramsite′s performance of raw material ratio and baking system were studied.The results showed that the rate of ceramsite cracking during roasting process and density of ceramsite can be decreased by adding ordinary clay and compound L，and the apparent density and strength of ceramsite can be decreased by increasing calcining temperature and the addition of ordinary clay，compound L and pulverized coal，and the strength of ceramsite can be increased by adding a suitable limestone.The lightweight ceramsite could be prepared if the raw pellets，which prepared with red clay，ordinary clay compound L，limestone and pulverized coal at the mass ratio of 85.5∶7.0∶3.5∶3.0∶1.0，were drying at 105 ℃ for 4 h，preheated at 450 ℃ for 30 min and calcined at 1 170 ℃ for 12 min.The key performance indexes of the ceramsite prepared in the industrial test all met the quality requirements of 500 grade ceramsite in GB/T 17431.1-2010，which indicated that the technology has the practical value of production and application.The research results have broken through the strict restrictions on the raw materials of lightweight ceramsite，which provided a new way for the high value-added utilization of high plastic red clay in metallurgical flux mine.

Key words: High plastic, Red clay, Lightweight ceramsite, Baking system