Abstract: In the tests of this paper,the setting-properities of high-density material of cement-tailing backfill at a different ratio has been done.After tests we got parameters of primary and final setting time.According to the obtained parameters of setting-properities of backfill slurry,the change of these mechanical properties and their laws are analyzed,in the meanwhile,all kinds of influence factors to setting-properities of backfill have made a essential analysis,which provide a certain instructive importance and reference to mines work of filling and analying the mechanics properities of backfill.