The invention relates to a living cell laser scanning co-focusing microscope imaging system, which is characterized by comprising a laser scanning co-focusing microscope and a fluorescent signal collecting device, wherein the fluorescent signal collecting device comprises a culture dish, a converging lens and a reflecting type narrow-band light filter, the converging lens and the reflecting type narrow-band light filter are arranged in the culture dish, the bottom of the culture dish is provided with a culture dish bottom plate used for placing cells to be tested, the converging lens is fixedly arranged on the culture dish through a lens clamping frame, the cells to be tested on the culture dish bottom plate are positioned on the focal plane of the converging lens, the reflecting type narrow-band light filter is positioned right above the converging lens, and an objective lens of the laser scanning co-focusing microscope is positioned right under the culture dish bottom plate. The living cell laser scanning co-focusing microscope imaging system has the advantages that the structure is compact, the precision is high, the fluorescent signal collection efficiency of the laser scanning co-focusing microscope can be effectively improved, the phototoxicity and the light bleaching degree are reduced, and a technical means is provided for obtaining reliable experiment results.