Peter Samuel Dempsey (born 31 March 1986) is an Irish racing driver from Ashbourne, County Meath.
Dempsey began his pro career in Formula BMW UK in 2004, finishing 22nd.
In 2005 he finished second in the Formula Ford Walter Hayes Trophy race and won the BRDC Golden Helmet.
In 2006 he finished third in Formula Ford UK and won the Walter Hayes Trophy.
He had no full-time drive in 2010 but participated in one American Le Mans Series race (the 2010 Petit Le Mans) and a number of high-profile Formula Ford races in the UK.