Objective To investigate the molecular mechanism of mmu-miR-672-5p in regulating apoptosis of placental chorionic trophoblast cells in rat. Methods Apoptosis of placental chorionic trophoblast cells was detected after overexpression or knockdown of mmu-miR-672-5p. After overexpression or knockdown of mmu-miR-672-5p, the expression of genes regulated by mmu-miR-672-5p was detected by RNA-seq. After setting the threshold and knocking down relevant genes by siRNA, the level of placental chorionic trophoblast cell apoptosis was determined. mmu-miR-672-5p targeting particular genes was verified by luciferase reporter assays. After overexpression of the gene of interest, the expression level of cleaved caspase 3 and the level of placental chorionic trophoblast cell apoptosis was determined by western blotting. Results After overexpression of mmu-miR-672-5p, the level of placental chorionic trophoblast cell apoptosis decreased (P< 0. 05). After mmu-miR-672-5p was knocked down, the level of placental chorionic trophoblast cell apoptosis was increased (P< 0. 05). After knockdown or overexpression of mmu-miR-672-5p, high-throughput sequencing reveled the differential regulation of multiple genes in placental chorionic trophoblast cells, including Zfp229、Zfp503、Slc4a5、Stk24、 Tmem106b、Bax、Adgrb3、Tmem63b、Pmp22、Mroh2a、Dsn1、Pramef25、Naaladl2、Clk2、 Stx16、Usp28、Clint1、 Jph4、Msl2、 Krtap8-1、Pkp2、Mllt3、Rai14 After knocking down the above genes, only knockdown of Bax caused a decrease in the level of placental chorionic trophoblast cell apoptosis (P<0. 05). After overexpression of Bax, the level of cleaved caspase 3 and the level of the placental chorionic trophoblast cell apoptosis increased (P<0. 05). After overexpression of mmu-miR-672- 5p, both the mRNA and protein levels of Bax decreased (P< 0. 05). After mmu-miR-672-5p was knocked down, both mRNA and protein levels of Bax increased (P<0. 05). In addition, mmu-miR-672-5p targeted the 3′-non-coding region of Bax (P<0. 05). After simultaneous overexpression of mmu-miR-672-5p and Bax, there was no significant change in the level of placental chorionic trophoblast cell apoptosis (P> 0. 05). After simultaneously knocking down mmu-miR-672-5p and Bax, there was no significant change in the level of placental chorionic trophoblast cell apoptosis ( P> 0. 05). Conclusions mmu-miR-672-5p decreased Bax expression by targeting its 3′-non-coding region, and subsequently inhibited the apoptosis of placental chorionic trophoblast cells.