Simon George Thomas (born 28 December 1963) is a Welsh former politician who was a member of Plaid Cymru.
He was a Member of Parliament (MP) for Ceredigion from 2000 to 2005, and an Assembly Member in the National Assembly for Wales representing Mid and West Wales between 2011 and 2018.
He resigned as an Assembly Member and his party membership on 25 July 2018, following arrest by police on suspicion of possession of indecent images.
On 3 October 2018, he pleaded guilty to three counts of making indecent images of children.
On 31 October 2018 he was given a 26-week jail sentence, suspended for two years.