Abstract: An optical imaging system (1) is configured for photographing a sample and includes a lighting module (11) and an imaging module (15). The lighting module (11) is configured for outputting excitation light, the excitation light is configured to excite the sample to generate excited light, the imaging module (15) comprises a time delay integration line scan camera (151), the time delay integration line scan camera (151) is configured to record the excited light. A biochemical substance detection system using the optical imaging system (1) is also provided, improving the detection flux.