An image forming apparatus includes an image holding member, a visible image detecting unit, a shielding part, a conveying passage, and a medium contact part. The visible image detecting unit includes a detecting part and detects a visible image, and the detecting part is disposed to face the image holding member. The shielding part is supported to be movable between a shielding position where the detecting part is shielded, and a detection permitting position where the detecting part is exposed. The medium contact part is supported to be movable between an entry position where the medium contact part enters a conveying passage, and a medium contact position where the medium contact part comes into contact with a medium and recedes from the entry position. The image forming apparatus moves the shielding part while interlocking with the movement of the medium contact part.