OBJECTIVE: To research the effect of low-doses long-term benzo(a)pyrene [B(a)P] exposure on miRNAs expression profile in lung tissue of mice and analyze the potential mechanism of miRNAs on the B(a)P-induced health damage.METHODS: Exposure mice were treated with 5 μg/kg B(a)P for 8 weeks by intragastrical administration.Control mice were treated with same volume of olive oil solvent.Then, all mice were fed for another 8 weeks without exposure.The total RNA was isolated from lung tissues of mice.The miRNAs expression profiles were detected by high-throughput sequencing technique and the signaling pathway was analyzed by DIANA-mirPath software.RESULTS: 74 miRNAs differentially expressed in the lung of mice after long-term low-dose B(a)P exposure.B(a)P-relevant differential expression of miRNAs were mainly involved in the signaling pathway of environmental information related signal transduction pathway, such as MAPK, ErbB, Wnt, TGF-beta, and mTOR signaling pathway.CONCLUSION: Low-dose long-term B(a)P exposure could specially alter miRNAs expression profiles.The signature of miRNAs expression described in this study provides potential targets for future clinical applications.