Vassal Abago Bagobagan Gadoengin (1 May 1943 – 15 December 2004)[1] was a political figure from the Pacific nation of Nauru.

Gadoengin was elected to parliament in 1997, winning the seat of Ruby Dediya and was re-elected in 2000.

He served as Minister of Finance in the cabinet of Bernard Dowiyogo in March 2001.

[2] In 2003 he lost his seat to newcomer Marcus Stephen, but regained it after the 2004 snap elections.

He was elected Speaker of the Parliament of Nauru twice: from December 2002 to January 2003, and again on 26 October 2004.