The electorate was created in 2002, replacing the abolished electorate of Pakenham, which had its namesake moved into Bass. It was widely considered to be a safe Liberal seat, and was to be contested by Shadow Treasurer Robert Dean, formerly the member for abolished Berwick. However, in a heavily publicised gaffe, it was discovered during the campaign that Dean was ineligible to stand as a candidate due to his enrolment having lapsed.  He was quickly replaced with Neil Lucas, the MLC for the corresponding upper house seat of Eumemmerring Province. In an upset result widely attributed to the Dean affair, Lucas was defeated by Labor candidate Tammy Lobato. Lobato was narrowly re-elected at the 2006 election, but was defeated at the 2010 election by Brad Battin.
Gembrook is a bellwether in state elections, having been won by the party winning government at every state election since its creation in 2002.