The invention discloses an infrared image confidence evaluation device and method based on an adaptive mesh, and mainly solves the problems that an existing method is incompatible to human eye visual perception, and is not high in evaluation efficiency and quality. The implementation scheme is characterized by 1) obtaining an actual infrared scene image and a synthetic infrared scene image; 2) segmenting the actual infrared scene image and the synthetic infrared scene image into M image blocks respectively; 3) calculating similarity indexes of the image blocks in the actual infrared scene image and the synthetic infrared scene image; 4) calculating weighting factor of the similarity index of each image block; and 5) calculating confidence of the synthetic infrared image according to the similarity index and the weighting factor. The method and device can evaluate different targets in the same synthetic infrared image, improves confidence evaluation efficiency and evaluation quality and can be applied to photoelectric scene digital simulation, semi-physical simulation system verification and synthetic infrared image quality evaluation.