Background: The hypothalamic-pituitary-tyhroid axis is directly affected by drastic changes in energy stores. The aim of the present study was to determine the effects of triiodothyronine (T3) treatment on cut-surface healing of remnant stomach with weight loss alterations after sleeve gastrectomy (SG). Methods: Thirty male Wistar Albino rats were divided into three groups: sham (n = 6), control (n = 12), and experimental (n = 12). Control and experimental group rats underwent sleeve gastrectomy. Experimental group rats received a single dose of T3 (400 mg/100 g) on the first postoperative day whereas control group rats received 0.9% NaCl. All rats were sacrificed on the seventh postoperative day. Results: In the group of rats receiving T3, levels of FT3 were significantly higher and that of FT4 were significantly lower compared with both the control and sham group rats (p <.05). No significant difference was found between control and T3 group rats in terms of weight loss (p >.05). Microscopic examination of the cut surface of remnant stomach in the control group rats revealed significantly more severe tissue necrosis, edema, and disruption of mucosal epithelium than in the T3 group rats (p <.05). On the other hand, bridging of the submucosal and muscular layers, tissue granulation, fibroblast accumulation, neoangiogenesis, and collagen deposition in the T3 group rats were significantly higher than in the control group rats (p <.05). Conclusions: Sleeve gastrectomy did not significantly alter thyroid hormone levels in short term. T3 hormone therapy seems to deliver constructive therapeutic effects for wound healing while causing no adverse effect on weight reduction.