An air leak detection system for chest tube collection systems includes a light emitting element, such as an LED, and a photodetector that can detect reflected light emission generated by the light emitting element. The air leak detection system can include a securement component, such as a transparent clip or adhesive, so that the air leak detection system is compatible with any conventional chest tube collection system. In certain embodiments, the light emitting element is positioned closer to the bottom portion of the water seal tube than the photodetector. In certain embodiments, the photodetector is positioned closer to a bottom of the water seal chamber than the light emitting element. In certain embodiments, the air leak detection system is part of a chest tube drainage system. A method of detecting an air leak in a chest tube collection system is also disclosed.