An image recording apparatus includes a conveying mechanism for conveying a recording medium in a conveying direction, and a scanning carriage including a recording head for and a detector. The detector detects a first edge and a second edge of the recording medium in a leading edge detection region and in an intermediate detection region located between the leading edge detection region and the trailing edge of the recording medium. The scanning carriage moves in a scanning direction orthogonal to the conveying direction. Moreover, the image recording apparatus includes a storing unit for storing a first position of the first edge and a second position of the second edge, which are detected by the detector. The image recording apparatus further includes a controller for controlling movement of the scanning carriage. The controller controls a moving speed of the scanning carriage, such that the detector detects across the recording medium in the scanning direction including the first edge and the second edge. The detector detects the first and the second edge according to the first position of the first and the second position of the second edge in a leading edge detection region.