On 7 April 1794, von Buseck was elected Prince-Bishop of Bamberg and ordained to the priesthood.
His nephew, Georg Karl von Fechenbach, the Prince-Bishop of Würzburg, consecrated him as a bishop on 16 August 1795 and he took office.
In the course of the German mediatization of 1802–1803, which saw the suppression of all the Holy Roman Empire ecclesiastical principalities, Bavaria occupied the former prince-bishopric on 29 September 1802 and annexed its territories.
However, until his death on 28 September 1805, von Buseck remained bishop of Bamberg, but bereft of any temporal power.
After his nephew's death in 1808, the See remained vacant until 1818,[2] by which time Bamberg had been elevated to an archbishopric following the Bavarian Concordat of June 1817.