Despite significant policy drives, the wide adoption of sustainable building (SB) is hindered by factors such as high upfront cost and long payback period. Business model (BM) innovation is therefore highly demanded to help SB professionals to cope with the challenges and convert the value of SB into profit. Nevertheless, few studies examined BM innovation in the building sector and factors influencing BM innovation for SB are unclear. This paper aims to identify the critical factors that propel companies to innovate BM for SB. First, a literature review and expert interviews were conducted to identify and filter the drivers for BM innovation within the SB context. Second, a questionnaire survey was conducted to collect data on the significance of the selected influencing factors from 132 SB professionals. Finally, a model based on fuzzy set theory was used to ascertain the critical factors influencing BM innovation for SB. Twenty-four critical influencing factors in six categories from the external environment and internal organization were finalized, namely, market and economic, policy and legislation, technology and industry structure, social-culture, entrepreneurship, and organizational learning. The findings illuminate the motivations when developing BM for sustainability and provide strategies on BM innovation for practitioners and policy makers.