This research aims to explore key factors of SMEs’ external collaboration and identifies the perceived factors affecting propensity for collaboration. Particularly, we focus on two factors – internal strategic activities geared towards open innovation and external collaboration partners, both of which are essential to establishing an external collaboration. We conducted a survey of Korean SMEs regarding their collaboration project experiences, and used logistic regression analysis to analyze the survey data. The research findings are expected to help understanding the complex open innovation mechanism in SMEs and to have meaningful implications for the development of their collaboration model.