A printing system having a first printer apparatus for forming an image on a first plane of a web having no feed holes and a second printer apparatus provided at a post stage of the first printer apparatus for forming an image on a second plane of said web. The first printer apparatus (P1) is operable to form a position-alignment mark (Rm) at a predesignated position on each page of a web (W). This position-alignment mark (Rm) is detected by mark detection means (16) of the second printer apparatus (P2). Control means (17) is provided for controlling an appropriate web transport speed so that both the generation timing of a web feed control signal (CPF-N signal) being generated with preset cyclic periods and the generation timing of a mark detection signal as issued from the mark detection means through detection of the position-alignment mark (Rm) are kept constant in phase. <IMAGE>
