Justina was the daughter of unknown parents. The date and place of her birth have not been found.
Her husband was Franz II Christoph von Khevenhüller und Hohen-Osterwitz. They were married, but the date and place have not been found. Their five known children were Sigmund VI (1597-1656), Maria Elisabeth (1608-1676), Sibylla (?-1635), Bartholomäus (?-1648) and Wolfgang Georg (?-1614).