The NGC 4631 Group is a poorly-defined group of galaxies in the Coma Berenices and Canes Venatici constellations. The brightest galaxy in the group is NGC 4631, a spiral galaxy that is seen edge-on from Earth.
Most studies place NGC 4631 and the interacting galaxies NGC 4656/NGC 4657 in the same group. The dwarf elliptical galaxy NGC 4627, which is a companion of NGC 4631, is also by default a member of the group, although it is not listed in most catalogs. Aside from these four galaxies, however, the determination of group membership is quite variable. The group lies in a relatively crowded part of the sky near the Virgo Cluster, so exact determination of the group membership is extremely difficult. Some studies have estimated that the NGC 4631 Group contains as few as 5 galaxies, while others place the estimate as high as 27. Additionally, it is unclear as to whether the galaxies near NGC 4631 and NGC 4656/NGC4657 form one large group or two smaller groups.