[en] Integral luminosities of 260 galaxies in the A 2634 cluster zone (up to B = 18.sub(m) 3) have been determined by direct photometric measurements of pictures obtained on the 40'' Schmidt telescope of the Byurakan Observatory, and the galaxy luminosity function has been constructed. Distribution chart of the measured galaxies has been presented. The differential luminosity function increases not monotonously but has a local maximum at 15.sub(m)8. This local maximum in the luminosity function is responsible for the break of the integral luminosity function curve represented by equations in the luminosity ranges of 15.sub(m)0 <= B <= 15.sub(m)9 and 15.sub(m)9 <= B <= 18.sub(m)3. Galaxy segregation in luminosity os observed in the cluster