Abstract: In cemented filling mining, cement is the traditional cementing material and takes 60 % ~ 80%of the total filling cost universally. The laboratory tests for blast-furnace slag of the third smeller of Jinan Iron&. Steel Group show that ground slag has a better cementing property and can replace parts of cement for cemented filling material. The field trial shows that the slag can replace 40%⁵0% of the cement and the cemented filling cost can be reduced by 19. 4% ~ 24.2 %. This paper introduces the tests of blast-furnace slag atZhangmatun Iron Mine, describes the process flowsheet and the expected benefits that can be obtained.