Objective To investigate the clinical effects of different drug treatment on early onset severe preeclampsia.Methods 80 patients with early onset severe preeelampsia were randomly divided into two groups:Pell horizon treatment( group A) 40 cases and phentolamine treatment (group B) 40 cases, blood pressure, serum Ca2+,Mg2+ concentration and protein in urine were observed before and after treatment in .Results The mean arterial blood pressure in medication over 24 hours compared with that before treatment were significantly decreased in two groups ( t = 2.351,2.315, all P < 0.05 ) ; After treatment reduced urinary protein was observed in two groups, before and after tratment there were no significant difference ( t = 1.289,1.287, all P > 0.05 ) ; The contents of Ca2+, Mg2+After treatment were higher than before treatment ( t = 2.298,2.311, P < 0.0) ; The time of average pregnancy in group A was significantly longer thar that in group B ( x2 = 3.714,P < 0.05 ) ;The number of Apgar score more than 8 points in group A was significantly higher than the group B( x2 = 3.784 ,P < 0.05 ).Conclusion Perdipine with magnesium sulfate had affirmative curative effect in the treatment of early onset severe preeclampsia,and it was deserved to be applied.