The 46-year-old actress and theatre director husband have three sons, Dashiell, 14, Roman, 11, and seven-year-old Ignatius and they adopted baby Edith last year.
Though the whole family dote on the new addition, they won't be extending their family any further, reported OK! magazine.
Asked if she will adopt again, Blanchett said: "No, I don't think we have any more rooms left in our house.
"We're surprised by how quickly our boys have accepted our little girl. They treat her like one of the family and that's really been beautiful for us to see."
"It's chaos. I wouldn't know how to describe it differently, but children are a marvellous form of chaos.