It is an object of the present invention to provide an optical module which can extract only light components satisfying predetermined conditions, and an imaging device comprising the optical module. The optical module (10) comprises a first plate-like optical element (4) formed with a ¼ wavelength plate portion (1) and a −¼ wavelength plate portion (2) alternately jointed together at a joint portion (3), and a second plate-like optical element (8) formed with a ¼ wavelength plate portion (5) and a −¼ wavelength plate portion (6) alternately jointed together at a joint portion (7), wherein the first plate-like optical element (4) and the second plate-like optical element (8) are parallel, and the ¼ wavelength plate portion (1) of the first plate-like optical element (4) and the −¼ wavelength plate portion (6) of the second plate-like optical element (8) are overlapped across a gap (9).