Abstract: To investigate the effects of traditional Chinese medicine extracts on oocyst sporulation of Eimeria in vitro, un-sporulated oocysts of three species of Eimeria were cultured in vitro with extracts of traditional Chinese medicine which were Phytolacca, Pulsatilla and Dichroa at different concentrations(25%，50%，100%) for 24 hours and 48 hours, respectively. Oocysts were observed with microscope and sporulated rate was calculated. The results showed that when the concentration of the three kinds of medicines was 50%, sporulated rates of E. tenella, E.necatrix and E.acervulina were 26.20%, 4.74% and 24.09% when cultured in Phytolacca, 57.95%, 10.74% and 20.74% when cultured in Pulsatilla, and 64.65%, 20.53% and 18.03% when cultured in Dichroa after 24 hours. Sporulated rates of E. tenella, E.necatrix and E.acervulina were 58.41%、40.89% and 31.45% when cultured in Phytolacca, 64.81%, 19.42% and 60.90% when cultured in Pulsatilla, 64.18%, 39.70% and 63.16% when cultured in Dichroa after 48 hours. There was a significant reduction in sporulated rate of oocysts cultured for 24 hours and 48 hours in drug groups compared with that of the control group. There were differences among the three drugs inhibited. Concentration of traditional Chinese medicine extracts being 100% showed the best effect in inhibiting sporulation, then was the concentration of 50%. There were inhibitory effects of the three kinds of traditional Chinese medicine extracts on oocyst sporulation in vitro of Eimeria to a certain extent. Inhibitory effect increased with the increase of drug concentration. Phytolacca showed the best inhibitory effect.