With the marginal profits of sportswear manufacturers have gradually shrunk, many sportswear manufacturers pursue a transformation of OEM (Original Equipment Manufacturer) to OBM (Original Brand Manufacturer). This study conducts an in-depth interview to investigate the strategy development and process of the transformation from professional OEM to OBM strategy in the small and medium-sized sportswear manufacturer. This study concludes that a good corporate image, or reputation can be as the key factors, strategies and implementations with the company's limited enterprise resources. The findings can effectively provide a reference for future academic research, enterprise development, and policy makers by relevant government or management and authorization.