This study aimed to understand what role teachers consider the immersive virtual field trip (VFT) system to play in primary school classrooms. There were 19 teachers' perceptions of immersive VFTs for educational purposes explored. The interview transcripts were analyzed using the phenomenographic method. The results showed that, for usability issues, three categories: lack of interaction, language affordance, and hardware and network problems, were generated from the teachers' concerns. The teachers proposed three ideas: instructional scaffolding, microscopic scale, and localized content, for immersive VFT systems and content design. Regarding learning influences, the teachers considered that the learning by immersive VFTs may provide the benefits of: enriching experiences, increasing motivation, understanding abstract concepts, and fostering inquiry learning. The teachers suggested five instructional approaches: advance organizer, learning extension, learning evaluation, collaboration, and role playing for the implementation of immersive VFTs in classrooms. These findings could benefit future development of immersive VFT learning systems.