The erector spinae plane block (ESPB) is described as a safe and effective alternative when epidural or paravertebral blocks are contraindicated by anticoagulation therapy. We present a case of subcutaneous hematoma after ESPB catheter placement. The patient received bilateral ESPB catheters for perioperative pain control. Postoperatively, the patient developed tenderness to palpation at the left catheter site. Physical examination revealed a well circumscribed, fluctuant mass that produced bloody material during incision and drainage. This case report describes hematoma as a potential complication of the ESPB. After the procedure, patients should be closely monitored for complications, including hematoma.