Tyzenhaus studied at the Jesuit College of Vilnius. As a young man, he served for the powerful Czartoryski family in their court at Wołczyn. At that time, Tyzenhaus befriended Stanisław August Poniatowski, who was born and educated at Wołczyn, as Czartoryskis were his uncles. After the election of Poniatowski to the throne of Poland–Lithuania (1764), Tyzenhaus became Court Treasurer of the Grand Duchy of Lithuania, the Starosta of Hrodna, and administrator of royal estates. He was elected to the Sejm of the Polish–Lithuanian Commonwealth in 1766.