With the rapid development of genetic modification technology, more and more transgenic crop lines have been successfully bred and widely applied in fields, but the environmental risks on the non-target organisms have been the cause of increasing concern worldwide. In this study, the effects of different transgenic Bacillus thuringiensis (Bt) rice (KMD producing single Cry1Ab protein as well as HH1 expressing fused Cry1Ab/Ac proteins) and their respective parental lines (non-transgenic rice:XSD and MH63) on the abundance dynamics and diversity of soil mites were investigated under field conditions. The results showed that transgenic Bt rice had no negative effect on the composition of soil mites. Only some specifically rare groups (<1%) and common groups (≥ 1% and <10%) of soil mites disappeared or appeared in paddy field soil due to the planting of transgenic Bt rice. Besides, the percentage of the common group of Epilohmannia belonging to Epilohmanniidae in the paddy field soil of transgenic Bt rice with single Cry1Ab (KMD) increased by 525% compared to the paddy field soil of its parental line (XSD). The abundance dynamics showed no significant differences, and the measured indexes of Shannon diversity (H'), Pielou evenness (J), and Margalef's richness (SR) of soil mites between the paddy fields of transgenic Bt rice (KMD and HH1) and their respective parental lines (XSD and MH63) throughout the growth season (P > 0.05). However, compared with the planting of transgenic Bt rice with a single Cry1Ab transgene, the planting of transgenic Bt rice with fused Cry1Ab/Ac transgenes resulted in significant increase in the abundance and genus richness of the soil mites (P < 0.05). It is presumed that the planting of transgenic Bt rice with fused Cry1Ab/Ac transgenes in contrast to single Cry1Ab transgene is advantageous for the occurrence and diversity conservation of non-target organisms (including soil mites).