Public technology transfer and technology commercialization are attracting worldwide attention, but the research on the commercialization of technology transferred from government-funded research institutes (GRIs) to small- and medium-sized enterprises (SMEs) is scarce. This study aims to identify and prioritize the factors contributing to the commercialization success of technologies transferred from GRIs to SMEs and to quantitatively present their importance. We proposed novel concepts of SMEs’ and GRIs’ technology commercialization proactiveness (SME TCP and GRI TCP) as two main success factors. We conducted hierarchical logistic regression analysis and decision tree analysis for 301 SME cases that adopted technology between 2013 and 2016 from Electronics and Telecommunications Research Institute (ETRI), a representative GRI in Korea. As a result, SME TCP was measured based on technology transfer expenditure (TTE), and frequency (TTF) was confirmed to be the most important factor. In particular, the success rate was higher when TTE exceeded 151 M KRW, or TTF was three or more. In addition, the success rate varied greatly depending on GRI TCP, namely the degree and the type of GRI researchers’ support. These findings can be used as primary data when establishing policies to promote cooperation between SMEs and other GRIs and provide practical implications for both technology providers and adopters.