The invention discloses a composite shooting system and a composite shooting method for improving the aerial image quality of an unmanned aerial vehicle. The composite shooting system comprises a plurality of cameras and a composite processing mechanism, wherein the plurality of cameras are disposed on the unmanned aerial vehicle and are collaborative; the composite processing mechanism is used for compounding images. The shooting method comprises the following steps: the plurality of cameras find views and shoot collaboratively, wherein the view-finding ranges of the cameras are overlapped; the composite processing mechanism compounds the images into one image. According to the composite shooting system and the composite shooting method for improving the aerial image quality of the unmanned aerial vehicle, the aerial image quality of the unmanned aerial vehicle can be effectively improved, various compounded images are provided, the fineness and the gradation sense of the images are enhanced, the details of the images are enriched, the colors are abundant, the outlines are clear, the depth of field is sharp and bright, the images can be favorably compared with images shot by a single lens reflex, the photographing modes are diversified, are even better than photographing modes of the single lens reflex in the aspects of color detail, black, white and grey contrast, depth of field, gradation, exposure balance and the like, and satisfy the demands of various images; the composite shooting system is low in load requirements for the unmanned aerial vehicle, does not affect the cruising ability of the unmanned aerial vehicle; the composite shooting system is simple in structure, convenient to mount and low in cost.