Abstract: A printing system includes: a host apparatus; and a printer as a device apparatus which is connected to the host apparatus. The host apparatus includes: a data amount determining unit which determines whether data of a printing target file exceeds a storage capacity of a receiving and storing memory of the printer; a starting command converting unit which converts a file transmission starting command to be transmitted to the printer from a batch transmission starting command to an on-demand transmission starting command when the data of the printing target file exceeds the storage capacity of the receiving and storing memory of the printer; and an on-demand transmission control unit which transmits a sub data file to the printer according to reception of the data requirement from the printer after transmission of the on-demand transmission starting command.