Erector spinae plane block (ESPB) is a newly emerging truncal block that can cover a wide range, from T1-2 to T8-10, for 10-12 h. The procedure is easy and safe, and presents a minimal risk of complications, compared with conventional regional block approaches. This report describes cases where ESPB provided effective analgesia after total mastectomy with lymph node dissection. Three patients underwent total mastectomy with sentinel/axillary lymph node dissection. After surgical procedure, continuous ESPB via catheter was performed for postoperative pain control. A bolus of 0.375% ropivacaine with epinephrine (1:200000) was injected through the indwelling catheter every 12 h. Postoperative pain score was maintained between 0 and 2. Total opioid consumption was minimal, and there was no requirement for rescue analgesics during the postoperative period. We believe that the ESPB can provide effective analgesia after total mastectomy with sentinel lymph node dissection.