What does it mean to dream about mummy?
A mummy in a dream often pictures the past preserved and unburied, an old hurt or memory that will not decay, or something kept long after its time.
Four ways to read it
Each reading below comes from a named tradition and a cited source, so you can see where it came from and decide what fits your dream.
Freud
Freud would read the preserved corpse as the past kept intact rather than laid to rest, a memory wrapped and stored. Its return may be the repressed refusing to decay. Ask what old thing you have preserved instead of mourning.
After Freud, The Interpretation of Dreams (Brill trans., 1913), public domain.Jung
Jung might see the mummy as a part of the self embalmed and held out of life, kept but not living. Its rising can mark old material seeking a true end or a new form. The dream may ask what you are unwilling to finally bury.
Jungian concept (our summary).Modern
Threat-simulation theory suggests the dreaming brain can stage the dead returning, the past coming back as a threat. Films and stories feed the familiar image. Notice whether the figure pursued you or simply would not stay buried.
Threat-simulation theory (our summary).Mythological
In Egyptian belief the body was preserved so the soul could carry on, and later tales turned the mummy into a curse that returns to punish the living. It marks the dead held against their natural rest. The image tends to weigh what you keep that ought to be released.
Rosmerta Publishing editorial synthesis (after Frazer; Brewer).