  NGC 663 is a young, moderately rich open cluster, known to contain one of the
largest fractions of Be stars among all galactic clusters. In this work we
present CCD uvby-beta photometry for stars in its central area. We have used
these data to obtain the main cluster physical parameters. We find that the
reddening is highly variable, with values ranging from E(b-y)=0.639+/-0.032 in
the central part to E(b-y)=0.555+/-0.038 in the south-east. The distance
modulus is found to be 11.6+/-0.1 mag.(2.1 Kpc), and the age log t=7.4+/-0.1
years (25+7/-5 Myr). The age obtained is consistent with the interpretation of
the Be phenomenon as an evolutionary effect.
