  We report CCD photometry and spectroscopy during 2006 outburst of the dwarf
nova SDSS J102146.44+234926.3 (SDSS J1021). The photographic plates from the
MAO, SAI and CrAO plate archives, which cover the position of the SDSS J1021,
were inspected for the presence of previous outbursts. We also present the
BVRcIc photometric calibration of 52 stars in SDSS J1021 vicinity, which have
V-magnitude in the range of 11.21-17.23m and can serve as comparison stars. The
large amplitude of the SDSS J1021 outburst of 7m, superhumps with a period
below the ''period gap'', rebrightening during the declining stage of
superoutburst, rarity of outbursts and obtained spectrum allow to classify this
object as a WZ Sge type dwarf nova.
