This study investigates the correlations among perceived organizational support (POS), self-efficacy, knowledge transfer, and innovative behaviors of employees in the information service companies of Taiwan and mainland China using goal-oriented behavior and social identity theory. A structural model was built, and data were collected through a survey conducted in two rounds, two months apart, during the COVID-19 pandemic. The results indicate that POS significantly affects innovation behavior and self-efficacy in both regions, and self-efficacy plays a key mediating role in the research model. However, the relationship between POS and knowledge transfer was non-significant for mainland China. The study also reveals that the culture of knowledge sharing in the organization can promote employees’ innovation, knowledge sharing behavior, communication, and knowledge transfer. The findings imply that managers should provide organizational support to improve employees’ innovative minds and self-belief, particularly during the pandemic. This research fills a theoretical gap by applying Western theories in an Eastern context and broadening the generalization of the theory. It provides practical implications for improving the quality of human resources by suggesting that managers should provide organizational support to improve employees’ innovative minds and self-belief, particularly during a pandemic. Additionally, it contributes to the literature by examining how cross-cultural differences affect the relationships among POS, self-efficacy, knowledge transfer, and innovative behavior. This study also enriches the literature about employees in particular regions and their service innovation behaviors.