Objective: To investigate the clinical efficacy of percutaneous catheter drainage (PCD) under the guidance of Color Doppler ultrasound in treatment of severe acute pancreatitis (SAP) with abdominal fluid collections. Methods: The clinical data of 131 SAP patients with confirmed fluid induced (type II) intra-abdominal hypertension during the course of SAP were collected. Of the patients, 65 cases underwent ultrasound-guided PCD (observational group), while the other 66 cases underwent conservative treatment (control group). The relevant clinical variables, efficacy indexes, and incidence of complications and mortality between the two groups were compared. Results: The pre-treatment data between the two groups were comparable. Observational group was superior to control group with regard to the time to disappearance of symptoms and signs, to blood amylase level recovery, and to diet resumption as well as the length of total hospital stay (all P<0.05). The urinary bladder pressure in both groups showed a decreased trend after treatment, but the decreasing speed in observational group was faster than that in control group (P<0.05). The incidence of complications was reduced and the effective rate of treatment was increased in observational group compared with control group (both P<0.05). There was no statistical difference in mortality between the two groups (P>0.05). Conclusion: Early PCD can reduce the abdominal pressure in SAP patients with abdominal fluid collections, decrease the incidence of complications and shorten the course of disease, but it has no significant effect on mortality.