Objective To study the effects of icariin (ICA) on the level of nitric oxide (NO) and malondialdehyde (MDA) in culture medium of fertilization(IVF)early porcine embryos in vitro, and to research both the relations among ICA, NO, MDA and the association with developmental ability of porcine IVF embryos. Methods NCSU-23 basic culture medium was used as the medium for control group, while ICA(0.6mg/L)supplemented medium was used as the medium for the experiment group. The reductive ferment method and thiobarbituric acid colormetry method were used to detect the nitric acid and MDA in media at interval duration of culture (0-48h,48-120h,120-168h). Results There were significantly different between experimental (342 embryos) and control (349 embryos) groups in the cleavage rate (74.84 vs 63.32%)(ICA vs control), the morrula and blastocyst rate (45.08 vs 34.10 %), and the blastocyst rate(23.38 vs 18.04%) at the intervals for 48 th, 120 th,168 th hour(EM>P/EM><0.01). During the culture process of porcine embryos, the concentrations for both NO and MDA in media kept increasing, while NO concentration in medium was higher in ICA group than that in the control group, the MDA concentration in medium was lower in ICA group than that in the control group, but there was no statistic significant(EM>P/EM>>0.05). 〖WTHZ〗Conclusion ICA can promote the developmental abilit