Oiva Emil Kalervo "Oippa" Tuominen (5 March 1908, Iitti – 28 January 1976, Helsinki) was a Finnish fighter ace and a Mannerheim Cross knight of the second class.

Oiva Emil Kalervo Tuominen was born in Iitti, in Southern Finland, on 5 March 1908.

Tuominen was promoted to Sergeant-Major with his score at 18, and became the first FAF holder of the Mannerheim Cross on 18 August 1941.

By April 1943 Flight Master Sergeant Tuominen had 31 victories, being transferred to HLeLv 34 equipped with the Bf 109G-2.

After the war, he worked, among other things, as a commercial pilot for the Imatran Voima company and as a taxi driver.