Abstract: Provided are an optical system for measuring optical characteristics and a device for measuring optical characteristics capable of acquiring a two-dimensional image close to visual observation in addition to measurement of optical characteristics of a measurement target. The optical system for measuring optical characteristics includes a first optical system (11) that captures an infinite conjugate image and a second optical system (12) that captures a conjugate image of a measurement target. The first optical system (11) and the second optical system (12) sharing a first lens group (G1) are arranged on two optical axes separated by an optical element (5) that deflects an optical axis, respectively, and are configured as one measuring optical system.