HMS Spark (pennant number P236) was a S-class submarine of the third batch built for the Royal Navy during World War II.

[2] For surface running, the boats were powered by two 950-brake-horsepower (708 kW) diesel engines, each driving one propeller shaft.

She survived the Second World War, spending between December 1944 and July 1945 with the Eastern Fleet, arriving at Trincomalee on 21 October 1944.

Spark was attacked by an enemy escort which dropped sixteen depth charges, but managed to escape damage.

Spark acted as tow for the midget submarine XE-1, which was assigned to attack the Japanese heavy cruiser Myōkō in Singapore Harbour as part of Operation Struggle.