Iain Simpson Stewart MBE FGS FRSE (born 1964)[1] is a Scottish geologist who is currently Jordan-UK El Hassan bin Talal Research Chair in Sustainability at the Royal Scientific Society in Jordan.

[2] Described as geology's "rock star",[3] Stewart is best known to the public as the presenter of a number of science programmes for the BBC, notably the BAFTA nominated[4] Earth: The Power of the Planet (2007).

In an interview with the Glasgow Herald, Stewart revealed that he initially struggled with geology: "I was a middling student, never really at the top of the class, nor at the bottom.

[10] Leaving acting behind, he studied geography and geology at Strathclyde University, graduating in 1986 with a first class honours Bachelor of Science degree.

He obtained his doctorate, entitled "The evolution of neotectonic normal fault scarps in the Aegean Region" in 1990 at the University of Bristol on research into earthquakes in Greece and Turkey.

[12] He left to become Jordan-UK El Hassan bin Talal Research Chair in Sustainability in 2021 on a four year secondment to the Royal Scientific Society, based in Amman.

His main research interests are in the broad area of Earth hazards and natural disasters, particularly in terms of identifying past major earthquakes, tsunamis and volcanic eruptions in the Mediterranean region.

[21] Stewart was appointed Member of the Order of the British Empire (MBE) in the 2013 Birthday Honours for services to geology and science communication.