To evaluate if percutaneous drainage of sterile fluid collections recurring after initial aspiration in acute pancreatitis yields better results than their conservative management. Fifty-eight patients with fluid collections in acute pancreatitis were followed up prospectively. Forty of them with sterile fluid collections that recurred after initial aspiration were randomly assigned to two groups of 20 in each. One group was initially treated with conservative management and the other group with prolonged catheter drainage. Patients with unsuccessful initial treatment were converted to more aggressive procedure. Outcome measure was conversion rate to more aggressive procedure. Conversion to more aggressive procedure was done in 11 and 3 patients treated conservatively and with catheter drainage, respectively (p = 0.02). Four and 11 patients had bacterial colonization of their fluid collections in conservative management and drainage group, respectively (p = 0.048). Conservative treatment was successful in all six patients with sterile liquid collections < 30 ml. However, this treatment was unsuccessful in all seven patients with multiloculated and liquid collections >100 ml. Prolonged catheter drainage is more efficient for management of recurrent sterile fluid collections in acute pancreatitis than is conservative treatment. Conservative treatment is successful for patients with small fluid collections.