Abstract: This study was aimed to verify fetus protection effects of altrenogest and delivery induction effects of 2 needles of half dose of cloprostenol on sows, in order to shorten their delivery interval. The abnormal parturient sows were treated with altrenogest orally for several consecutive days. Postponed delivery sows were injected by 2 needles of half dose of cloprostenol (2 needles interval 6 h) to induce parturition. The results showed that the proportion of deliveries was 0% in the test group treated with altrenogest orally and 0.2% in the control group. The proportion of births in the test group was 74% after the first injection of cloprostenol with half dose during 22 to 32 h, while 57% in the control group. The proportion of births in the test group was 2% with the first injection of cloprostenol after 56 h, while 9% in the control group. The altrenogest can effectively inhibit early delivery in sows, and injection of 2 needles of half dose of cloprostenol can effectively improve induced delivery and reduce the proportion of delayed delivery.