An image reading apparatus includes: three line sensors having filters, respectively, different in spectral sensitivity, and arranged in a subscanning direction with a distance therebetween to scan an original in the subscanning direction; a platen arranged between the original and the three line sensors; a mover moving the platen at a rate relative to the three line sensors, the rate being different from that of the original relative to the three line sensors; a noise pixel detection processor detecting a noise pixel from each of the three data output from the three line sensors; a color detector detecting a color of each noise pixel from the three data; and a determiner validating a result of detection by the noise pixel detection processor when a color of the noise pixel and that of a pixel neighboring the noise pixel form a predetermined combination.