Lev Leviev is an Israeli-Russian businessman, born in 1956 in Tashkent (then in the Uzbek SSR) and emigrated to Israel as a teenager, who built one of the largest privately-held diamond manufacturing and rough-trading operations of the late twentieth and early twenty-first centuries. He is principally known in the trade for breaking the De Beers Central Selling Organisation monopoly on Russian rough in the 1990s, for taking direct positions in African production, and for the eponymous luxury retail brand Leviev that operated boutiques in London, New York, Singapore and Dubai.

His commercial breakthrough came in 1996, when his firm secured a direct rough-supply agreement with Alrosa, the Russian state diamond producer, bypassing De Beers's CSO. The arrangement made Leviev one of the largest direct buyers of Russian rough through the late 1990s and 2000s, and it positioned his manufacturing operations (large polishing facilities in Israel, Armenia and India) as one of the few non-De Beers-aligned mid-stream actors at scale.

His African positions included direct stakes in mining concessions and processing in Angola (a long-running Catoca-region position), Namibia (offshore marine recovery), and historically in Zimbabwe (a position eventually divested in the 2000s amid the political situation there). His operations have been the subject of significant press scrutiny, including investigative coverage in the Wall Street Journal, the New York Times and the Financial Times, particularly regarding sourcing practices in Angola.

The Leviev retail brand opened on Old Bond Street in London in 2006 and at other locations in subsequent years, positioned at the very high end of the loose-stone and signed-jewellery market. The retail business was scaled back through the 2010s.