The buildup factors for high energy neutrons of 14.1 MeV in a two-layered medium are calculated using the Monte Carlo method. Neutrons from planar monodirectional source are assumed to be incident on the surface of the multilayered-medium. A systematic study is carried out for the two cases: carbon-iron medium and iron-carbon medium. The value of the buildup factor is strongly affected by the order of arrangement of the layers in the medium and on the relative thickness of each layer. A fitting formula is given to represent the buildup factor inside the medium in an analytical form.