Gastroparesis is a disorder of gastric motility that results in delayed gastric emptying. Up to 58% of patients with diabetes mellitus may have diabetic gastroparesis, a syndrome characterized by nausea, vomiting, early satiety, and bloating. The pathophysiology of this disorder is not completely understood, but it is believed to include fundic dysaccommodation, a decrease in gastroduodenal pressure gradient and antral hypomotility. In addition to antral and fundic dysfunction, patients with diabetes may typically have pyloric dysfunction or spasm. Treatment consists of a change in diet to small volume, frequent meals and the use of the prokinetic agents. This case report describes the four patients with severe diabetic gastroparesis whose symptoms persisted despite of dietary changes and the use of prokinetic agents in high doses. All of them were treated with pyloric injection of botulinum toxin and three had significant symptomatic and scintigraphic improvement.