Simon Tensing de Cruz (born 2 February 1954 in the United Kingdom) is a Singaporean diplomat and is currently the Ambassador Extraordinary and Plenipotentiary of the Republic of Singapore to the Russian Federation.
De Cruz graduated from the University of Singapore with a degree in political science in 1979 and joined the Singaporean Ministry of Foreign Affairs the same year.
In 1996, he was appointed as Ambassador of Singapore to the Philippines, a position he held until 1999, when he was appointed as the island republic's Ambassador to Myanmar in 2000 and held that position until 2004.
After serving in a department of the Singapore Foreign Ministry, he was appointed as the High Commissioner of Singapore to Papua New Guinea on 29 May 2006.
On 24 September 2008, de Cruz was appointed as Ambassador of Singapore to Russia, and presented his Letter of Credence to President of Russia Dmitry Medvedev on 27 February 2009.