In China, historic blocks^① are undergoing extensive regeneration and facing challenges of touristification and commercialization, with regard to which the impacts of B&Bs are not yet thoroughly discussed. Based on a field survey conducted in the Pingjiang Historic Block in Suzhou, this study examines the participation of the local government, residents, B&B operators, and tourists in shaping B&B spaces. The results show that B&B operators take a dominant position in this process, while the local government acts as both regulator and developer. In contrast, local residents remain largely passive with limited participation. While leading to the touristification of the historic block, the development of B&Bs has contributed to the conservation and adaptive reuse of historic and cultural resources. Finally, the study concludes that ensuring the sustainable development of B&Bs in historic blocks requires both more effective regulation of the local government and more active participation of native residents.