Datuk M. Karathu (born 23 February 1943) is a Malaysian football manager and former player.
He also has coached the Kinta Indian Association (KIA) team in the FAM Cup.
As head coach, his success at club level includes winning the first ever FA Cup for Perak over the fancied Selangor team in 1990.
In 2011, he guided Kelantan to win the Sultan Haji Ahmad Shah Cup title and 2011 Super League Malaysia championship.
Karathu resigned as head coach of Kelantan, ending his second spell with the East Coast team in 2011, after failing to defend their 2010 Malaysia Cup title by losing to Terengganu FA in the quarter-finals of the 2011 Malaysia Cup tournament.