Abstract: The relationship between backfilling quality efficiency benefit (referred to as“BQEB”) is a problem that is difficult to avoid in the theoretical design and engineering implementation in backfilling mining.Also,a quantitative characterization method of the BQEB relationship has not yet been established.In this study,for solid non dense backfilling and dense backfilling mining,the concept,characterization theory and optimal controll method of BQEB has been put forward.Take the process of gradual compaction of the backfill under the action of mechanical tamping and the compaction of the overlying rock in the gob as the link,an analysis model based on the relationship between the solid dense backfilling BQEB,backfilling process,backfill parameters and compact state of the backfill is constructed.The relationship among BQEB is expounded,the meaning,solving process and calculating formula of BQEB are presented with theoretical analysis method.Based on the single factor variable analysis method,the influencing laws of four backfilling process factors,namely tamping times,single tamping times,dumping time of single backfilling shield and stack height,as well as two backfill factors,namely angle of repose and initial packing density of backfill,are studied,and four types of BQEB relationships are obtained.According to the BQEB relationship law and combined with the key parameter design process of backfilling mining,a BQEB optimal control method is proposed.The BQEB analysis of the T3292 backfilling face in Tangshan Mine shows that the surplus tamping times were implemented during the backfilling ming,thereby the backfilling efficiency and benefit were reduced.It is recommended to optimize the backfilling materials and reduce the tamping times,so as to ensure the backfilling effect and achieve a better mining efficiency and benefits.