Abstract: Disclosed are a tunnel-inspection image acquisition device, a tunnel-inspection system and a tunnel-inspection method. With a plurality of CCD cameras, a plurality of auxiliary light sources and a fixing bracket, wherein the CCD cameras and the auxiliary light sources are fixed on the fixing bracket, and the plurality of CCD cameras are fixed on the same ring, a center of the ring is located at a center of a circle of the tunnel in working condition, distances between the plurality of CCD cameras and a tunnel lining are the same and overall shooting angles of the plurality of CCD cameras cover a range of the tunnel lining; meanwhile, with the cooperation of a computer, a monitor, a synchronous encoder and a data collector on a defect detecting mobile platform, functions such as the synchronous shooting, the disease identification, the real-time splicing and display of the tunnel can be achieved.