Objective To investigate the neuroprotection role of muscone at early phase after traumatic brain injury(TBI) in rats.Methods A total of 120 SD rats were randomly divided into sham group,TBI group and muscone (0.9 mg/kg) group,with 40 rats per group.Each group was examined at postinjury four different time points (12 h,24 h,3 d and 7 d),each including 10 rats.Left-sided fluid percussion TBI models were utilized in the study.Sham rats underwent craniotomy only.Rats in muscone group received intraperitoneal injection of muscone immediately and then every day after injury.Instead,equal volume of saline was used in TBI group.Rat learning and memorizing ability,morphological changes of brain tissues and cell apoptosis were observed after injury.Results After injury in rats,learning and memorizing ability was reduced,brain tissue morphology changed,and cell apoptosis was raised,peaked at 3 d and decreased at 7 d.At postoperative 12 h,24 h,3 d and 7 d,rats in muscone group versus TBI group presented better results in learning and memorizing ability (12.1 ± 2.5 vs.7.4 ± 1.5;14.8±1.0 vs.10.4±2.0;15.4±2.0 vs.11.3±1.0;9.8±2.0 vs.5.7±1.4) (P＜0.05),cell apoptosis (2.32 ± 0.21 vs.3.48 ± 0.23;2.67 ± 0.42 vs.3.87 ± 0.34;3.46 ± 0.23 vs.4.27 ± 0.42;3.16 ± O.24 vs.3.82 ± 0.2t) (P ＜ 0.05),and brain tissue morphology.Conclusion Muscone is associated with significantly reduced cell apoptosis and improved neurological function at early phase after TBI in rats.