The invention discloses a device and method for detecting panel strip shapes, and belongs to the technical field of metal panel detection. The device is characterized in that as is shown in the picture 1, a machine frame (3) is installed above a transverse striding conveying roller way (4), a rail is arranged below an upper beam (2) of the machine frame (3), and a first distance measuring instrument (A), a second distance measuring instrument (B) and a third distance measuring instrument (C) which serve as a whole are installed inside the rail below the upper beam (2) side by side and can be driven by a stepping motor (1) to do reciprocating movement. The distance between probes of every two adjacent distance measuring instruments is T. The direction in which a panel (5) is conveyed on the conveying roller way (4) is perpendicular to the direction of the rail below the upper beam. The operating method comprises the steps that firstly, in the process of conveying the panel, the three distance measuring instruments do once stroke on the rail by double width value of the panel to measure the perpendicular distance between each point in the panel and the distance measuring instruments; secondly, the measured distance value is recorded; thirdly, the detected and recorded data of each point are corrected and calculated. The device for detecting the panel strip shapes has the advantages of being simple in structure, low in manufacturing cost and reliable in operation, the strip shapes can be detected under the dynamic situation, and high measuring precision can be achieved.