According to Abbe, oblique illumination in imaging systems allows the entrance of higher spatial frequencies into the system’s aperture and thus increases the resolution power of it. We have extended the idea to Mirau digital holographic microscopy to obtain super-resolution in 3D images. High magnification Mirau objectives are expensive and low magnification ones suffer from low lateral resolution. We have already demonstrated the increase in lateral resolution through introducing a transparent microsphere into the working distance of the Mirau objective. In this paper, we show that by applying inclination to the illumination direction in Mirau system the resolution can be further improved. We have tested the technique on different samples and verified the increase in lateral resolution and edge sharpness in the presence and in the absence of the microsphere.