The spread of the COVID-19 pandemic has gradually promoted blended teaching based on Small Private Online Course (SPOC) as a common teaching practice in most higher education institutions. Teachers play a critical role in the successful implementation of blended teaching. Questions regarding the factors that influence teachers' implementation strategies for SPOC-based blended teaching in higher vocational colleges, positively or negatively, are raised. This research investigated 63 English as a foreign language (EFL) teachers from four higher vocational colleges in China who are implementing SPOC-based blended teaching, encoded the obtained data at three levels, explored factors influencing EFL teachers' implementation of SPOC-based blended teaching, and constructed a theoretical model of the factors influencing teachers' implementation of SPOC-based blended teaching in which SPOC-based teaching intention is a pre-influencing factor, whereas the school incentive mechanism and curriculum platform satisfaction serve as situational influencing factors. This study can help EFL teachers improve the implementation of SPOC-based blended teaching and further optimise SPOC-based blended teaching policies and measures for stakeholders in practice.