The first CCD UBV(RI)c photometric study in the area of the
doubtful open cluster NGC 2129 is presented. Photometry of a field
offset 15 arcmin northward is also provided, to probe the Galactic
disk population toward the cluster. Using star counts, proper motions
from the UCAC 2 catalog, colour-magnitude and colour-colour diagrams we
demonstrate that NGC 2129 is a young open cluster. The cluster radius
is 2.5 arcmin, and across this region we find evidence of significant
differential reddening, although the reddening law seems to be normal
toward its direction. Updated estimates of the cluster fundamental
parameters are provided. The mean reddening is found to be
E(B-V) = 0.80 ± 0.08 and the distance modulus is (m-M)o =
11.70 ± 0.30. Hence, NGC 2129 is located at 2.2 ± 0.2 kpc from
the Sun inside the Local spiral arm. The age derived from 37
photometrically selected members is estimated to be approximately 10
million years. These stars are used to provide new estimates of the
cluster absolute proper motion components.