If the old person is male – depending on the gender of the dreamer – he will stand for either the self or the animus.
If female then she will signify the great mother or the anima. All father figures, or representations of the father, will often appear old as if to highlight their remoteness.
A group of old people often appears in dreams. Usually this signifies the traditions and wisdom of the past – things sacred to the ‘tribe’ or family. Older people usually stand for our parents even though the dream figures may bear no relationship to them.