SM UB-63 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 23 July 1917 as SM UB-63.

UB-63 was sunk on 28 January 1918 by British warships HMS W.S. Bailey and HMS Fort George at 56°10′N 2°0′E / 56.167°N 2.000°E / 56.167; 2.000 with depth charges. All 33 crew members perished in the attack.

UB-63 was ordered by the GIN on 20 May 1916.

She was built by AG Vulcan of Hamburg and following just under a year of construction, launched at Hamburg on 26 May 1917. UB-63 was commissioned later that same year . Like all Type UB III submarines, UB-63 carried 10 torpedoes and was armed with a 8.8 cm (3.46 in) deck gun. UB-63 would carry a crew of up to 3 officer and 31 men and had a cruising range of 8,420 nautical miles (15,590 km; 9,690 mi). UB-63 had a displacement of 508 t (500 long tons) while surfaced and 639 t (629 long tons) when submerged. Her engines enabled her to travel at 13.3 knots (24.6 km/h; 15.3 mph) when surfaced and 8 knots (15 km/h; 9.2 mph) when submerged.

Date	Name	Nationality	Tonnage	Fate
15 September 1917	Santaren	United Kingdom	4,256	Sunk
3 November 1917	Haelen	Belgium	3,290	Captured as prize
8 November 1917	Lindhardt	Denmark	225	Sunk
15 November 1917	Stargard	Norway	1,113	Damaged