Objective To explore the significance of ultrasound in choosing the delivery modality in 200 cases scarred uterus gravida′s second deliveries .Methods The study selected 200 cases late pregnancy gravidas who had once uterine incision delivery history and analyzed clinical data retrospectively ,all of them were chosen from September 2010 to September 2013 in our hospital . All cases were taken by transabdominal ultrasound or transvaginal ultrasound firstly ,then taken by transabdomina transvaginal ul‐trasound ,finally contrast obsenved the transabdomina transvaginal ultrasound detections with their caesarean section observations , meanwhile observe how the uterus scar ranking affect the delivery consequence .Results (1)A total of 200 cases had higher uterus scars visualization ratio(100 .0% ) than ransabdominal ultrasound (92 .0% )and transvaginal ultrasound(96 .5% )(P<0 .05);con‐trasting the transabdomina transvaginal ultrasound with the caesarean section observations ,there was no significant difference(P>0 .05) .The grading diagnosis coincidence of transabdomina‐transvaginal ultrasound was 89 .74% .(2)The UD rate ,the bleeding vol‐ume during operation and the 24 hours postoperative bleeding volume of scarred uterus gravida grade Ⅱ and grade Ⅲ were signifi‐cantly higher than grade Ⅰ (P<0 .05) .Conclusion Transabdomina transvaginal ultrasound can effectively improve the diagnosis coincidence rate of uterine scar detection and can help to chose the better delivery mode according to the scars healing .