This paper examines the Start-up Success of Spin-off and Symbiosis Company (SSC) using Entrepreneurial Orientation (EO) and Support Service. Notwithstanding the extensive study on start-up firms and Support Service, there is a missing link on how EO impacts Start-up Success, particularly in Malaysia case study. To address such limitation, this paper proposed that Start-up Success of SSC will be improved by EO and Support Service. A total of 120 SSC in Peninsular Malaysia were employed as respondents and data were analyzed using PLS-SEM analysis. The empirical results showed that EO is positively related to Start-up Success and intensify the potentials of Support Service as a moderator. As most of the related literature highlights the importance of Support Service, this study brings new perspectives on how EO is also significant in improving the Start-up Success. In addition, the critical discussion provided in this paper is expected to contribute to the body of knowledge on entrepreneurship studies and act as a future reference on the EO, support service, and SSC.