Abstract: The purpose of this study was to explore the protein component information of sika deer antler in different growth stages, and provide a theoretical basis for the exploration of effective active substances in antler. In this study, the proteome characteristic and alterations at 6 time points(10, 20, 40, 60, 130 and 360 d after casting) throughout antler growth cycle were analyzed based on label-free and bioinformatics methods. The result showed that sika deer antler was rich in protein, and the protein content in antler on 10, 20, 40, 60, 130 and 360 d were 65.35, 70.90, 74.00, 82.25, 56.00, 28.02 mg·g^-1, respectively. A total of 636 proteins were successfully identified based on label-free, of which 218 proteins involved in protein synthesis, developmental process, cytoskeleton, transport were found to be significantly differentially expressed in different growth stages of antler. The protein expression in velvet horns in different growth stages has their own characteristics, which lays a theoretical foundation for the screening of pharmacological active components in sika antler horn and the development of velvet-related products.