Objectives: This in vivo study aims to investigate the effects of Ankaferd Blood Stopper® (ABS) which is a recently developed topical hemostatic agent on tendon healing using a rat Achilles tendon injury model. Materials and methods: Twelve male Wistar-Albino rats were used in the study. Right legs of the rats were assigned as the study group, and left legs were assigned as the control group. Under anesthesia, bilateral Achilles tendon injuries were created and repaired surgically. To the surgical sites, 1 mL of ABS for the right side and 1 mL of serum physiologic solution for the left side were applied. Animals were euthanized on the 21st postoperative day, and tendon samples were collected from the extremities. Histological analyses were performed according to the semiquantitative tendon scoring system (Bonar Scale). Results: Total tendon healing scores were significantly poorer in the study group compared to the control group. Although there were no significant differences between the groups in terms of tenocyte morphology, degree of ground substance staining, and vascularity, the collagen morphology scores were significantly poorer in the study group. Conclusion: In our study, application of ABS had histologically negative effect on tendon healing in rats. However, further biomechanical and immune histochemical studies are required to support these results.