A dual-mode optical molecular imaging navigation apparatus with a switchable field of view, and an imaging method thereof, are provided in the embodiments of the disclosure, the apparatus including: a camera module configured to perform a color imaging and a fluorescence imaging; a switching module configured to switch between an open imaging mode and an endoscopic imaging mode as per imaging requirements; an open imaging module configured to perform observation and imaging with a large field of view; an endoscopic imaging module configured to perform observation and imaging with a deep field of view; a data processing module configured to provide a camera control software and image capturing, processing and display method; and a support module configured to support and connect the navigation apparatus.