The image forming apparatus comprises: a print head including a plurality of nozzles which eject droplets of a radiation-curable ink onto a recording medium; a conveyance device which causes the print head and the recording medium to relatively move to each other in a relative conveyance direction of the recording medium by conveying at least one of the print head and the recording medium in a direction substantially perpendicular to a width direction of the recording medium; an irradiation device which irradiates a radiation to the droplets of the ink, the droplets having landed on the recording medium; and a control device which controls the irradiation device so that the radiation is irradiated to a first ink droplet while a second ink droplet is in flight, the first ink droplet having been previously ejected from one of the nozzles in the print head and having landed on the recording medium, the second ink droplet being ejected from the same one of the nozzles so as to overlap with or make contact with the first ink droplet on the recording medium.