Objective To study the effects of low molecular heparin combined with ulinastatin in the treatment of acute pancreatitis (AP).Methods A total of 135 patients with AP were randomly and evenly divided into groups A,B and C.The three groups were treated with conventional therapy.Group A was additionally treated with low molecular heparin,group B with ulinastatin and group C with the said two drugs.Eight days after the treatment,the time of obvious relief of symptoms,effects and the changes in intestinal mucosal barrier function and inflammatory factor among the three groups were compared.Results After the treatment,the remission rate in group A was 80.00%,and the severe rate 13.33% and the operation rate 6.67%;those in group B were 82.22%,11.11% and 6.67% respectively,and those in group C were 95.56%,2.22% and 2.22% respectively;the remission rate in group C was significantly higher than that in groups A and B(P < 0.05) and the severe rate was lower than that in groups A and B;the diamine oxidase (DAO),d-lactic acid and urine L/M in the three groups decreased significantly (P < 0.05),and the sequence of the decrease from high to low was group C,group B and group A (P < 0.05);the post-treatment contents of TNF-α and IL-1 decreased significantly (P< 0.05),the contents of IL-10 increased greatly (P< 0.05),the changes in group C were greater than those in groups A and B (P< 0.05).Conclusion Low molecular heparin combined with ulinastatin has better effects in the treatment of AP than single drug,can significantly improve intestinal mucosal barrier function in patients,and reheve inflammatory reaction;it is worthy of clinical popularization.