According to one embodiment, an ink-jet image forming apparatus includes an ink-jet head which ejects water-based ink and form an image on a surface of a recording medium, a medium conveying unit which conveys the recording medium, a solution applying unit arranged further on an upstream side in a recording medium conveying direction than the ink-jet head and which applies water solution to a surface of the recording medium on which an image is formed, and a controller configured to calculate an application amount of the water solution to apply the water solution to the recording medium at 1% to 6% of weight of the recording medium and control an application operation to the recording medium.