Dennis Geoffrey Jensen (born 28 February 1962) is a former Australian politician. He was elected to the House of Representatives at the 2004 federal election, winning the Division of Tangney for the Liberal Party. Jensen lost Liberal preselection for the 2016 federal election, and subsequently resigned from the party to stand as an independent. In August 2017 he joined the fledgling Australian Conservatives party. Jensen has a PhD in materials science from Monash University, and before entering politics worked as a CSIRO researcher. He is known for questioning the anthropogenic causation of climate change.