  We study the optical properties of the Kehagias-Sfetsos (KS) compact objects,
characterized by the "Ho\v{r}ava" parameter $\omega_{_{KS}}$, in the presence
of plasma, considering its homogeneous or power-law density distribution. The
strong effects of both "Ho\v{r}ava" parameter $\omega_{_{KS}}$ and plasma on
the shadow cast by the KS compact objects are demonstrated. Using the weak
field approximation, we investigate the gravitational lensing effect. Strong
dependence of the deflection angle of the light on both the "Ho\v{r}ava" and
plasma parameter is explicitly shown. The magnification of image source due to
the weak gravitational lensing is given for both the homogeneous and
inhomogeneous plasma.
