No. 1 Operational Training Unit (No. 1 OTU) was an operational conversion unit of the Royal Australian Air Force (RAAF) during World War II. Formed in December 1941 at RAAF Station Nhill, Victoria, it relocated to RAAF Station Bairnsdale in mid-1942, and then to RAAF Station East Sale the following year. No. 1 OTU's primary role was to train aircrew for multi-engined aircraft operations.