Abstract: The aim of this study was to discuss the effect of PGI2 analogue iloprost on in vitro development of porcine embryos. In this study, at different times（0, 24, 48, 72 h）, iloprost with different concentrations（0, 0.2, 0.5, 1.0, 2.0, 5.0, 10.0 μmol·L-1）was added into the porcine zygote medium 3(PZM3) to observe the effect of iloprost on porcine IVF embryos and to screen the best additive dosage for embryo culture, blastocyst number and blastocyst cell number were counted at 156 h after fertilization. The speed of embryo fat metabolism and related genes(cox2, creb，pparδ, pdk, cpt2) expression level were tested for understanding the mechanism of iloprost promoting embryonic development. The results showed that addition of 2.0 μmol·L-1 iloprost at 48 hours after fertilization could significantly (P<0.05) improve the blastocyst rate (28%vs16%, P<0.05) and blastocyst cell number (49.42 vs 28.22, P<0.05), significantly accelerate fatty acid degradation speed (P<0.05) and promote the expression of lipid metabolism related genes(cox2, creb，pparδ, cpt2). However there’s no significant change in glucose metabolism related genes (pdk) expression level. These results demonstrates that iloprost can enhance the in vitro developmental capacity of porcine embryo by promoting fatty acid degradation.