PURPOSE: To provide the low-price scanning type optical microscope by decreasing the kinds of lens members in use.

CONSTITUTION: This scanning type optical microscope is equipped with a light source 1, an objective 8 which converges the light emitted by the light source on a sample, two deflectors 4 and 5 which are arranged between the light source 1 and objective 8 so as to scan the sample optically with a converged light spot, a pupil transmission optical system 6 which is arranged between the two optical deflectors 4 and 5 so that the two optical deflectors 4 and 5 are optically conjugate to each other, and a pupil projection system 7 which is arranged between one optical deflector and the pupil of the objective 8 so that they are optically conjugate to each other; and at least some of the lenses constituting the pupil projection optical system 6 and pupil transmission optical system 7 are composed of lens members of the same kind.