A protective tube arrangement for a piston-cylinder unit includes a substantially disk-shaped carrying cap and a protective tube which has axially projecting crenellations and free portions formed between the crenellations. First and second axially acting securing elements axially fix the protective tube to the carrying cap by positive engagement. Each of the securing elements is formed by a wrapped binding element which is wrapped around the protective tube over the crenellations and tightened between the crenellations over the free portions so that the binding element defines secant segments through the indentation of the imaginary contour of the protective tube between the crenellations in the free portions of the protective tube, which secant segments form a positively engaging arrangement for the carrying cap.