Objective To study the diagnosis and treat of premature rupture of membranes combined with abruption. Methods Selected 46 cases patients with placental abruption from 2007 March to 2013 Januay,and 18 cases patients with placental abruption,the other was 28cases. Retrospective analysis the the predisposition,the relationship between premature rupture of membranes and abruption,and the influecse on mother and baby. Results Premature rupture of membranes was the best predisposition of abruption( 39. 1%). The rate of abruption with premature rupture of membranes was 8. 7%( 18 /207). The rate abruption without premature rupture of membranes was 2. 6%( 28 /1086). Abruption reaulted to bloody amniotic fluid and mild asphyxia neonatorum. Conclusion Premature rupture of membranes can easily result abruption. The physicians should take care of premature rupture of membranes. Type B ultrasound and cardiac care can improve the diagnosis,reduce the adverse reaction.