ObjectiveTo design a method for observing pulmonary microcirculation in vivo in a native tissue environment, due to the high incidence of lung diseases and the advantages of animal experiments in vivo.MethodsTen BALB/c male mice were randomly divided into group A and group B, with five mice in each group. A self-made apparatus was used to control the movement towards local lung tissues in order to get a stabilized observation plane, and then a 5-minute video was shot with laser confocal scanning microscope. During the filming, the mice in group A were injected with fluorescein isothiocyanate-dextran via the tail vein, and the mice in group B were injected with green fluorescent protein-platelets (extracted from the blood of tie2-cre&rosa26-tomato-EGFP transgenic black C57 male mice). The data of group A was used to observe the lungs perfusion and the damage to tissue by this method, and the data of group B was used to observe the movement of platelets.ResultsImage of lung structure obtained by this method was clear and stable. Mean areas of alveolus in an instant and at the 30th, 60th, 120th, 180th, and 300th second were (1 603±181), (1 588±183), (1 528±363), (1 506±353), (1 437±369), (1 549±307) μm2, respectively, and there were no significant differences between each time point (P>0.05). The video was smooth, the rapid movement of platelets was recorded and the particles were clear and without tailing; after the observation, hematoxylin-eosin staining showed no obvious damage to the lung tissue.ConclusionThe method can be used for the observation and research of the lung microcirculatory system in the living state of the mouse, and provides a methodological basis for studies of other lung diseases in vivo.