To better understand the function of oar-miR-150 in the ovine granulosa cells (GCs) during the estrus cycle, the five turpan sheep were selected for detection of the expression of oar-miR-150 in follicular and luteal ovaries, respectively. Then the granulosa cells treated with oar-miR-150 mimics or negative control (NC) were analyzed by qPCR to assess the expression of genes involved in steroidogenic and apoptosis. Expression of oar-miR-150 was increased in follicular phase compared with that in luteal ovaries. STAR was a target gene of miR-150 with oar-miR-150 mimic or inhibitor and luciferase reporter assay. Overexpression of oar-miR-150 promoted expression of bax, bcl2 and Casp3 expression and declined the expression of STAR, Cyp11a1 and HSD3B1 in vitro. Taken together, these results demonstrate that the oar-miR-150 promote GCs apoptosis through modifying the expression of genes involved in progesterone synthesis.