The invention, which relates to the technical field of tire detection, discloses a detection device and a production line. The detection device comprises a rack, a tire supporting assembly, a liftingdetection assembly arranged at the rack, an ultrasonic detection assembly, and a control assembly. The tire supporting assembly is arranged at the rack; a to-be-detected tire sleeves the tire supporting assembly; and the tire supporting assembly is configured to realize expansion and rotation of the to-be-detected tire. The ultrasonic detection assembly is connected to the lifting detection assembly; the lifting detection assembly is configured to drive the ultrasonic detection assembly to reciprocate in a vertical direction and a central axis direction of the to-be-detected tire; and the ultrasonic detection assembly is configured to detect a cord layer area of a certain section of the to-be-detected tire and the position of the cord layer area. The tire supporting assembly, the lifting detection assembly and the ultrasonic detection assembly are all electrically connected to the control assembly. The detection device is used for detecting the position of the cord layer in the tire and determining whether cord layer deviates relative to the center of the tire or not and whether the deviation amount is within an allowable range or not.