The invention discloses a labeling device of a pharmaceutical production line. The labeling device comprises a rack, and an unrolling device, a body paper roller, a guiding roller assembly and a medicine bottle positioning assembly are arranged on the rack. The unrolling device is located on the upper portion of the rack, the body paper roller is located on the lower portion of the rack, the guiding roller assembly is rotationally arranged in the middle portion of the rack, the guiding roller assembly is connected with a transmission assembly, and the transmission assembly is driven by a drive mechanism. The unrolling device comprises a support, a rotary supporting part is rotationally arranged on the support, and detachable baffles are arranged at the two ends of the rotary supporting part. The guiding roller assembly comprises a guiding roller, a friction roller, a drive roller and a pinch roller. The labeling device is simple in structure and capable of rapidly labeling medicines, an adjusting mechanism on the upper portion of the unrolling device can carry out adjusting and fixing according to the size of a label center paper cylinder, and using flexibility is improved.