Provided is a method of extracting properties of a layer on a wafer, the method including emitting electromagnetic waves to a lower surface of the wafer, detecting a first electromagnetic wave, that passes through a target layer on an upper surface of the wafer, and a second electromagnetic wave, that is reflected from the target layer, among the electromagnetic waves to obtain data including information about the first electromagnetic wave and the second electromagnetic wave, and separating a first pulse of the first electromagnetic wave and a second pulse of the second electromagnetic wave from each other in the data and obtaining property data of the target layer.