The invention discloses an apparatus and method for route planning based on a PM2.5 healthy trip. The apparatus comprises three parts of a vehicle-mounted PM2.5 detector, an information transmission module, and a server terminal, wherein the information transmission module includes a GPS module and a GPRS module; the server terminal includes a route planning module; and the PM2.5 detector is mounted on a floating vehicle and is connected to the information transmission module, which is connected to the server terminal. A mobile device of a user can easily access data in the server terminal by means of a browser. According to the method, an improved Dijkstra algorithm is adopted, an integrated PM2.5 concentration is mainly taken as impedance, and a minimum total concentration is taken as a target. A healthy trip is planned according to an optimized function taking a PM2.5 optimal route as the target.