Peroral endoscopic myotomy has recently been developed and performed on patients with good results. To evaluate the technical feasibility of peroral endoscopic full-thickness and partial thickness myotomy in a porcine model. Eighteen criollo pigs were randomly assigned to 2 groups: group A (partial-thickness myotomy) and group B (full-thickness myotomy). The mucosal defect proximal to the myotomy site was left open. On the seventh postoperative day the pig was euthanized and follow-up surgical exploration was performed. The duration of each procedure, postoperative progression of the animal, complications, and anatomopathologic findings were registered. The procedure was viable in all the pigs. The mean surgery duration was 81±35.3min (group A 51.11±11.12, group B 111±22.61; P