Susan Lesley Griffiths MS (born 1960), known as Lesley Griffiths, is a Welsh Labour politician serving as Trefnydd of the Senedd since 2021. She worked as a secretary to John Marek and the constituency assistant to Ian Lucas, successive Members of Parliament for Wrexham, and was elected to the Senedd from the Wrexham constituency in 2007. She has held a number of cabinet positions in the Welsh Government. In December 2009 she was appointed Deputy Minister for Science, Innovation and Skills.