Objective To evaluate the efficacy and safety of COOK cervical dilatation balloon for induced labor in full -term pregnancy . Methods There were 98 cases of cervical ripening and induced labor by using COOK balloon from January 2014 to April 2015 ( experimental group ) and 130 cases of cervical ripening and induced labor by using oxytocin from January 2010 to September 2013 ( control group ) .The cervical scores , childbirth way , and adverse reactions were compared between the two groups . Results After the removal of the balloon, the cervical scores in the experimental group increased from (2.38 ±0.70) points to (6.15 ±0.96) points (t=31.412, P =0.000).The rate of vaginal delivery in the experimental group (79.6%, 78/98) was significantly higher than that in the control group [62.3%(81/130),χ2 =7.910, P=0.005].The incidence of chorioamnionitis in the control group was 5.4% (7/130), which was significantly lower than that in the experimental group [18.4% (18/98), χ2 =9.647,P=0.002).The other adverse reactions in two groups had no statistical difference (P >0.05). Conclusions Use of COOK cervical dilation balloon is a safe and effective method to promote cervical ripening .In combination with artificial rupturing membrane or intravenous infusion of oxytocin can improve the success rate of full -term pregnancy induced labor .