Abstract: The settlement of unclassified tailings waste rock compound filling body is a complex continuum mechanics loading process of non-Newtonian fluid and solid mixture，so it is difficult to obtain the settlement laws through the theoretical derivation or experience.In order to investigate the settlement of unclassified tailings waste rock compound filling body in Huibaoling Iron Mine，the similarity model test method is adopted to make the indoor simulation experiment on composite filling body with different proportions (height) of unclassified tailings and waste rock.The results showed that the proportion of waste rocks in compound filling body has a decreasing function with the total settlement amount.The fitting of total settlement amount of the compound filling body with time shows a decreasing logarithmic relationship among them.And the fitting curve significantly declined at 15d，so the settlement of compound filling approached to be stable after 15d，and roof cementation can be operated.After contrast on the time that required by settlement of compound filling with different proportions of waste rock，compound filling body with 1/2 ratio of waste rock has the fastest settlement.

Key words: Unclassified tailings, Waste rock, Compound filling body, Settlement law, Model test