  We perform an analysis of the luminosity functions (LFs) of two types of
ringed galaxies -- polar-ring galaxies and collisional ring galaxies -- using
data from the Sloan Digital Sky Survey (SDSS). Both classes of galaxies were
formed as a result of interaction with their environment and they are very rare
objects. We constructed LFs of galaxies by different methods and found their
approximations by the Schechter function. The luminosity functions of both
types of galaxies show a systematic fall-off at low luminosities. The polar
structures around bright ($M_r \leq -20^m$) and red ($g-r > +0.8$) galaxies are
about twice as common as around blue ones. The LF of collisional rings is
shifted towards brighter luminosities compared to polar-ring galaxies. We
analysed the published data on the ringed galaxies in several deep fields and
confirmed the increase in their volume density with redshift: up to z$\sim$1
their density grows as $(1+z)^m$, where $m \gtrsim 5$.
