To reduce the size of an image recorder of ink jet recording system at a low cost by sharing one pretreatment liquid coating means among a plurality of transfer paths thereby eliminating the inconvenience of providing a coating means for each transfer path.

Recording region of a sheet 13 from a first feed unit 10 or a sheet 55 from a second feed unit 60 is coated with pretreatment liquid containing a compound for making coloring agent in recording liquid (ink) insoluble by means of a coating roller 22 and then an image is recorded by means of a recording head 41. A plurality of transfer routes are selected in correspondence with the case when the pretreatment liquid is applied or not applied, and when recording is performed on one side or both sides of the sheets 13 and 55. A transfer path (common transfer section) 62b is shared by these transfer routes and the coating roller (coating means) 22 is provided only for the transfer path 62b. When the transfer route is selected, coating/recording operation can be carried out depending on the case by single print job. Since only one of a plurality of transfer routes requires the coating roller 22, size can be reduced at a low cost.