We report on a high-resolution metal-clad waveguide scanning microscopic method with a diffraction-limited resolution. This microscope can be operated in both TM and TE waveguide modes with radially and azimuthally polarized beams, respectively, and allows both refractive index and topography of dielectric objects to be evaluated at high resolution and sensitivity. We emphasize the performance of this microscopic method from calibrated 3D polymer microstructures with rectangular, disk, and ring shapes.