Inkjet printer (1) operable to print a print substrate made of textile, paper or plastic material, or the like, and provided with a sliding transfer surface (10) to feed the print substrate (2) in a feed direction (9); a printing device (17) arranged above the transfer surface (10) to define, on the transfer surface (10), a printing station (19); suction means (20) arranged below the transfer surface (10) to maintain the print substrate adhering to and stationary with respect to the transfer surface (10) during sliding; and an adjustment assembly to adjust planarity of the transfer surface (10).