Otto Kamillus Hugo Gabriel Count of Bray-Steinburg (* 17 May 1807 in Berlin; † 9 January 1899 in Munich) was a Bavarian diplomat and politician. He was a son of the diplomat François Gabriel Count of Bray who was of French origin.
Bray-Steinburg was taught in the Wilhelmsgymnasium in Munich and then studied law at the universities of Göttingen and Munich.
He then served as a Bavarian diplomat in Diplomat in Vienna, Paris and Athens. In 1843-59 Bray was with interruptions the Bavarian ambassador in Sankt Petersburg. In 1846/47 and again in 1848/49 he was Bavarian foreign secretary, during his second term he also served as President of the Council of Ministers, a title equivalent to Prime Minister of Bavaria. In 1859/60 Bray was appointer Bavarian ambassador in Berlin, then he returned to Vienna as ambassador. In 1870 King Ludwig II. appointed Bray again Minister of State of the Exterior and President of the Council of Ministers. In this position Bray was leading the Bavarian delegation for the negotiations of the Bavarian accession to the German Empire and managed to secure a privileged status for the Kingdom of Bavaria within the Empire (Reservatrechte). Within the Empire the Kingdom of Bavaria was able to retain its own railways, postal service, diplomatic body and even its own army, which would fall under Prussian command only in times of war.
In 1871 Bray resigned since he was in opposition to the Kulturkampf and then served again as Bavarian ambassador in Vienna until 1897.