A refractive power measuring method is disclosed wherein a pattern plate 8 is disposed at a certain position in a measuring optical path in a measuring optical system 1, a measuring light emitted from a measuring light source 5 is received by a photosensor 9 through the pattern plate 8, a soft contact lens TL is disposed at a certain position in the measuring optical path, and a change of a pattern light received by the photosensor 9 is obtained to determine optical characteristic values of the soft contact lens. According to this method, the soft contact lens TL is disposed in a wet state at a certain position of the measuring optical path and scattered light resulting from scatter of the measuring light on a surface of the soft contact lens TL is received by the photosensor 9, then a state of scatter of the scattered light is determined from a change of a received light signal outputted from the photosensor 9 and there are obtained optical characteristic values when the received light signal is below a preset value.