Diamond Valley may refer to:

• Diamond Valley, Queensland, a rural locality
• Division of Diamond Valley, Victoria
• Shire of Diamond Valley, a former local government area in Victoria

• Diamond Valley, Alberta, a town formed via the amalgamation of the towns of Black Diamond and Turner Valley

• Diamond Valley (California), a valley in the Plains of Leon in Riverside County, California
• Diamond Valley Lake, a reservoir in Riverside County, California
• Diamond Valley (Nevada)
• Diamond Valley (Washington County, Utah)

• Diamond Valley College, a public co-educational school in Diamond Creek, Victoria, Australia
• Diamond Valley United SC, a soccer club based in Greensborough, Victoria
• Diamond Valley Football League, former name of the Northern Football Netball League, Diamond Creek, Victoria
• Diamond Valley Railway, a ridable miniature railway at Eltham Lower Park, Eltham, Victoria
• Motu Patlu & The Race to The Diamond Valley, an Indian animated TV film based on the animated TV show Motu Patlu