Handu is a family business located in Yunnan Province, which mainly sells building materials. The company was established in 2015. With the outbreak of the COVID-19 pandemic, many companies have been affected. Then Handu still maintained their profits during this COVID-19 pandemic. The company still faces fierce market competition, and the company is still affected by the COVID-19 pandemic. In this study, the researcher hopes to analyze the competitive advantage of Handu during the pandemic through the collected data. Researcher will conduct case studies through in-depth interviews, direct and indirect observations, and field notes with owners, employees, and customers. The results of this study provide a mini-model theory to demonstrate Handu's competitive advantage during the COVID-19 pandemic. These latent variables include business model innovation, language problem, recruitment problem, quality control, working experience, trusting, marketing promotions, supporting leadership, communication skill, employees training, service performance, working arrangement, Word of Mouth (WOM), product quality and favorable price.