As China's economy and society keep expanding, the significance of business English in worldwide communication remains progressively crucial. Ensuring that China's business English talent training meets global standards is a priority. It has, therefore, become crucial and time-consuming to figure out how to help Chinese students enhance their business English writing skills. Zhang Xuexin, a Chinese professor at Fudan University, proposed the PAD (Presentation-Assimilation-Discussion) Class Model. Since it was presented, many academics and educators have supported it. This study involved 50 undergraduates from a Chinese university, including 25 in the experimental and control classes respectively. The 12-week teaching experiment was followed by interviews with a few students from the experimental class to investigate the influence of the PAD Class Model on the overall score and sub scores of Chinese students' business English writing, as well as the acceptability of the PAD Class Model. Through the analysis of the pre- and post-tests by SPSS, the results indicate that the utilization of PAD Class Model can substantially raise the overall score and the sub scores of content, language, appropriateness, grammar, and organization for undergraduate business English writing. Furthermore, by assessing the interview findings of the experimental class, compared to the conventional teaching model, PAD Class Model serves a more conspicuous role in boosting students' interest in Business English writing, and PAD Class Model is universally accepted by students.