Abstract
Open Source Software (OSS) is the software of which source code is open to public, and then the users can study and improve them corresponding to the application and market needs. This research conducted the questionnaire survey to IT companies in Japan, investigating how OSS utilization and development contribution affect the business growth of companies, which were presented in the JASMIN National Conferences in 2013 and 2014. In this study, we conducted t-test on the averages to analyze differences between respondent groups with Yes (1) or No (0) of utilization and development contribution, and groups by company profiles.