An image forming apparatus to print at least one of a plurality of test images and texts at various print concentration levels such that confusion of a user due to a change of a print concentration level is prevented, and a method of controlling the same. The method of controlling an image forming apparatus includes receiving confirmation of a print concentration level to print an image and printing at least one of test images and texts having predetermined print concentrations according to a normal print mode and a toner conservation mode, according to the received confirmation of the print concentration level.