Karl von Miltitz (c. 1490 – 20 November 1529) was a papal nuncio and a Mainz Cathedral canon.
His Saxon heritage, however, made him a natural liaison between the papal court and Elector Frederick the Wise.
On 3 September 1518 Pope Leo X decided to bestow on Frederick the papal Golden Rose of Virtue — an award with attendant religious privileges to deserving princes, with the aim of securing the support of Frederick the Wise in suppressing the attacks of Martin Luther on indulgences in the Church.
He met with Luther in Altenburg on 5–6 January 1519, and negotiated a tentative settlement to the controversy: Luther would remain silent on the indulgence issue, write a conciliatory letter to the Pope and write and publish a tract supporting papal authority.
He accidentally drowned in the Main River near Groß-Steinheim on 20 November 1529 and was buried in Mainz Cathedral.