This study makes the research on the relationship of EWOM, brand image and customers' purchase intention based on the purchase decision model and the samples focus on Hefei city in Anhui province. The specific effect and relationship could take the assessment of the specific dimensions for these three variables. EWOM owns the specific dimensions of positive valence, content and intensity. Brand image also gets the detailed dimensions of brand identity, brand personality and brand behavior. Meanwhile, the purchasing intention of customers also has the dimensions of risk, service of customers, experiences of shopping and perception of products. According to the collected investigation data resources, it shows that EWOM owns a highly significant relationship with positive direction with brand image and it also owns a highly significant influence and positive relationship with the purchase intention for costumers. Besides, brand image also owns a highly significant influence on the purchase intention for the customers. Lastly, this study proposed a model of the relationship among these three variables and intensifies the purchase decisions for customers.