SM UB-143 was a German Type UB III submarine or U-boat in the German Imperial Navy (German: Kaiserliche Marine) during World War I. She was commissioned into the German Imperial Navy on 3 October 1918 as SM UB-143. She was surrendered to Japan on 1 December 1918 and served in the Imperial Japanese Navy as O-7 until 1921, when she was broken up in Yokohama.