PURPOSE: Postoperative pancreatic fistula (POPF) after pancreatectomy is one of the severe postoperative adverse events. We aimed to clarify the outcomes of a strategy for POPF after left-sided pancreatectomy with one-step endoscopic ultrasonography-guided drainage (EUSD) and percutaneous drainage (PCD) based on the wall status of collected fluid. METHODS: From January 2012 to September 2017, 90 of 336 patients developed grade B/C POPF and were retrospectively analyzed. Primary outcome measures were the technical and clinical success and resolution rates. Secondary outcome measures were time from surgery to intervention, and time from intervention to discharge/resolution or stent/tube removal and adverse events. RESULTS: Seventeen patients underwent EUSD and 73 patients underwent PCD for POPF. The technical success rates were 100% in both the EUSD and PCD groups. The clinical success and resolution rates in the EUSD group were 100%, while those in the PCD group were 98.6%. The time from surgery to intervention was significantly longer in the EUSD group than in the PCD group (20 vs. 11 days, p < 0.001). The time from intervention to discharge/resolution was significantly shorter in the EUSD group than in the PCD group (11 vs. 22 days, p < 0.001/10 vs. 20 days, p < 0.001). The time from intervention to stent/tube removal was significantly shorter in the PCD group than in the EUSD group (20.5 vs. 873 days, p < 0.001). Adverse event rates were similar in the two groups (11.8% vs. 5.5%). CONCLUSION: A drainage strategy for POPF based on the wall status of collected fluid is appropriate.