In the context of digital transformation in the cultural and heritage sector, many museums are undergoing digital- ization. This qualitative study explores the digitalization status in the selected cases, underpins the decisions behind their digitalization practices, and identifies the factors that affect the decisions. The Swedish National Museum, Hallwhyska Museum, and Gävle Museum are selected as the bounded cases for this study. Applying the Digital Curation Lifecycle Model, this study conceptualizes the process mapping for digitalization projects; employing the attribution theory, this study identifies the internal and external factors affecting digitalization decisions.  As a multiple case study with a qualitative perspective, the data is collected through multiple sources, includ- ing interview data and web content retrieved from the selected museum’s websites. Following the research tradi- tion of organizational attribution, this study first collects and examines the digitalization practices of the selected museums; with the assistance of the lifecycle model, the practices are dismantled into a list of actions to concep- tualize the process mapping for digitalization projects and to identify the critical decisions at each stage; and then based on the interview data and the empirical evidence, this study identifies the factors affecting the decisions with the theoretical support of organizational attribution theory.  This study’s outcome brings insights into the institutional aspect of performing digitalization activities, thus contributing empirical evidence to future research in this field. The findings of this study indicate that the attribu- tion of museums’ digitalization decisions is complicated and can be affected by multiple factors and can be mul- tiple attributed. By reflecting on the process mapping and attribution process, this study tries to underscore the importance of contextuality and underpin the emerging trend in museums’ digitalization practices.