  The ninth part of the OGLE-III Catalog of Variable Stars (OIII-CVS) comprises
RR Lyr stars in the Small Magellanic Cloud (SMC). Our sample consists of 2475
variable stars, of which 1933 pulsate in the fundamental mode (RRab), 175 are
the first overtone pulsators (RRc), 258 oscillate simultaneously in both modes
(RRd) and 109 stars are suspected second-overtone pulsators (RRe). 30 objects
are Galactic RR Lyr stars seen in the foreground of the SMC.
  We discuss some statistical features of the sample. Period distributions show
distinct differences between SMC and LMC populations of RR Lyr variable stars,
with the SMC stars having on average longer periods. The mean periods for RRab,
RRc and RRe stars are 0.596, 0.366 and 0.293 days, respectively. The mean
apparent magnitudes of RRab stars are equal to 19.70 mag in the V-band and
19.12 mag in the I-band. Spatial distribution of RR Lyr stars shows that the
halo of the SMC is roughly round in the sky, however the density map reveals
two maxima near the center of the SMC.
  For each object the multi-epoch V- and I-band photometry collected over 8 or
13 years of observations and finding charts are available to the astronomical
community from the OGLE Internet archive.
