ABSTRACT Film-based fluorescent sensors have become an important field of sensor research due to abundant acquirable signals, real-time monitoring, ease of miniaturization and integration, where chemical sensitive films are the most vital component of the sensor devices. In this feature article, we introduce hardware structures of film-based fluorescent sensors following the examination/investigation of the recent progress of such sensors with perylene bisimide (PBI) derivatives as sensing fluorophores in the films. PBI derivatives were specially chosen because of their outstanding chemical, photochemical and thermal stabilities, as well as their unusual high fluorescence quantum yields. And finally, we provide a prediction about the future developments and challenges of this emerging field.