Objectives: This study aims to investigate the efficacy of tetracalcium phosphate (TTCP) on fracture healing in rat femurs. Materials and methods: Forty-two female Wistar Albino rats were randomized into two groups (Group 1 and Group 2, n=21 for each). The left femur of all animals was fractured by osteotomy after deep anesthesia with ketamine. Additional procedure was not applied to the rats in Group 1. Rats in Group 2, following osteotomy, were applied to the fracture line approximately 2 mL TTCP. The animals were sacrificed at Weeks 1, 2, and 3 after surgery (seven animals were sacrificed from each group each week) and the broken femurs were removed. The femurs were examined first radiographically and second histopathologically. Results: Radiologically, callus maturity and bone union increased with time in both groups. However, no significant differences were found regarding callus maturity and bone union in weekly comparisons (anteroposterior plain: p=0.53, p=0.37, p=0.42, lateral plain: p=0.26, p=0.42, p=0.87). Histopathologically, the fractures healed normally as the weeks progressed in both groups. The histological scores of Group 2 were higher at Weeks 1, 2, and 3. In the evaluation, no significant difference was found between the groups in terms of histological scores except for the first week (p=0.024, p=104, p=462, respectively). Conclusion: Although there was no statistically significant difference in the histological evaluation of both groups, except for the first week, the histological scores of Group 2, which underwent TTCP in all weeks, were higher. According to the results of this study, we believe that TTCP may be beneficial, particularly in the early stages of fracture healing.