To evaluate the effect of Tri-staple technology and slow firing using the Endo-GIA endoscopic linear stapler.The cardiac and pyloric portions of porcine stomachs were divided using the endoscopic linear stapler with different reload types. A total of 8 min of waiting time was employed during firing in the slow-firing group and no waiting time was employed in the normal-firing group. The shape of the staples was then evaluated. The length of the staple line and serosal laceration was also determined.There was a moderate negative correlation between tissue thickness and secure staple formation. Tri-staple reloads (purple, black) offered more secure staple formation compared with Universal green reload. Although slow firing enhanced secure staple formation, its effect was greater when using green reload, compared with Tri-staple reloads. Significantly shorter staple line length and longer serosal laceration was observed in the thick tissue. Although the cartridge type did not influence lengths of the staple line or serosal laceration, both were better in the slow-firing group.Tri-staple reloads offered more secure staple formation compared with the Universal reload. Although slow firing improved staple line shortening and serosal laceration, its effect on secure stapling was relatively small when using Tri-staple reloads.