Abstract: With the increasing demand for high-quality and professional teaching staff in basic education in the new era, online training has gradually become a key approach to promoting teachers’ professional development and addressing the problem of uneven distribution of teachers. However, the effectiveness of online training depends on various factors, among which the quality of training design is crucial, whose mechanism of action, unfortunately, remains underexplored. To address this issue, a hypothetical model, based on Holton’s training evaluation research framework and the theory of transactional distance, is constructed, with training design as the independent variable, transfer motivation the mediator, and training mode the moderator. The results of a follow-up survey of 1,124 primary and secondary school teachers using the Process plugin to fit and validate the model reveal that training design not only directly influences the effectiveness of online training but also exerts an indirect effect through transfer motivation. Furthermore, this indirect effect is moderated by the online training mode. Compared with the synchronous mode, the impact of training design on the effectiveness of online training is more pronounced in the asynchronous mode. Therefore, optimizing training design is one of the most important ways to enhance the effectiveness of online training.

Key words: teachers’ online training, training design, effectiveness of online training, transfer motivation, online training mode