RFA Wave Knight is a Wave-class fast fleet tanker of the Royal Fleet Auxiliary (RFA) of the United Kingdom tasked with providing fuel, food, fresh water, ammunition and other supplies to Royal Navy vessels around the world.

The Wave-class tankers are a class of fast fleet tankers in service with the Royal Fleet Auxiliary. The class is tasked with providing fuel, food, fresh water, ammunition and other supplies to Royal Navy vessels around the world. There are two ships in the class, RFA Wave Knight and RFA Wave Ruler. The ships were ordered to replace the aging Ol-class tankers RFA Olna and RFA Olwen. The two vessels have seen service in a number of locations, including anti-drug and hurricane relief operations in the Caribbean Sea, anti-piracy activities around the Horn of Africa, and deterrent patrols in the South Atlantic. As of early 2022, both ships were earmarked for "extended readiness" status.