SM UC-64 was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy () during World War I. The U-boat was ordered on 12 January 1916, laid down on 3 April 1916, and was launched on 23 January 1917. She was commissioned into the German Imperial Navy on 22 February 1917 as SM UC-64. In 15 patrols UC-64 was credited with sinking 26 ships, either by torpedo or by mines laid. UC-64 was mined and sunk in the Dover Strait on 20 June 1918.
A Type UC II submarine, UC-64 had a displacement of when at the surface and while submerged. She had a length overall of , a beam of , and a draught of . The submarine was powered by two six-cylinder four-stroke diesel engines each producing (a total of ), two electric motors producing , and two propeller shafts. She had a dive time of 48 seconds and was capable of operating at a depth of .
The submarine had a maximum surface speed of and a submerged speed of . When submerged, she could operate for at ; when surfaced, she could travel at . UC-64 was fitted with six mine tubes, eighteen UC 200 mines, three torpedo tubes (one on the stern and two on the bow), seven torpedoes, and one Uk L/30 deck gun. Her complement was twenty-six crew members.