  In this article, we study the neutron stars with antikaon condensates and
their radial oscillations. We incorporate the antikaons $(K^-,\bar{K}^0)$
within a relativistic mean field theory with density dependent couplings. A
transition to the kaon condensed phase is treated as a second order phase
transition for different possible antikaon optical potentials. Then, we solve
the structure equations of stars and calculate the fundamental and higher order
frequencies of their radial pulsations. We study the eigenfunctions of
different radial modes for a $2M_\odot$ star with equations of state having
different potential depths of antikaons. We also study the large frequency
separations for the $2M_\odot$ star. We find distinct features of the
appearances of antikaons on the eigenfunctions. The shape of the eigenfunctions
corresponding to the radial perturbations is affected due to the appearance of
the antikaons, but for the pressure perturbation, the shape remains unchanged.
