SM UB-49 was a German Type UB III submarine or U-boat in the German Imperial Navy () during World War I. She was commissioned into the German Imperial Navy on 28 June 1917 as SM UB-49. UB-49 served mainly in the Mediterranean. In the Austro-Hungarian Navy she was listed as SM U-80. In eight wartime patrols she sank 40 ships totaling and one escort. After the Armistice with Germany UB-49 returned to Kiel via Norway. Handed over to the United Kingdom on 16 January 1919, she was broken up in Swansea in 1922.