The purpose of the article is to explore brand value in the era of sharing economy platform based on prosumption logic. This study used Charmaz's Constructivist Grounded Theory to analyze prosumers' reviews randomly collected 23 sharing economy platform brands from Baidu Reputation. After initial coding analysis, focus coding analysis and theoretical coding analysis, the brand value dimension structure model and the brand value dimension path model were constructed. We found that web 2.0 platform brand should pay full attention to the dominant role played by the prosumers, because the prosumers also play an important role in the brand as well as its value co-creation mechanism. And the brand should fully recognize the importance of competitors so as to enhance the brand value. It could dramatically raise the brand value by encouraging band evangelism and brand citizenship behavior. Additionally, this study is the first to come up with a new construct of brand value under the prosumption logic with its own five dimensions. All constructs and the categories are based on the existing concepts. The new core concepts and categories are prosumption experience, competitor association, prosumer image, prosumption outcome quality, perceived justice, competitive price, cumulative satisfaction, prosumer trust, brand future prediction, brand and prosumer attachment, business partner, using intention after being recommended, brand worship, prosumer worship, attacking competing brand, altruistic behavior, brand support and development behavior.