Borloo was elected to the French National Assembly as a Miscellaneous Right candidate representing the Nord's 21st constituency in 1993.

He was a founding member of Ecology Generation in 1990, but he later joined the Union for French Democracy led by François Bayrou.

In that role, he introduced a five-year plan of social cohesion, which was centered around three axes: equal opportunity, housing and employment.

He announced plans to set up a "republican, ecologist, and social alliance", with a view to becoming a candidate in the 2012 presidential election.

Despite being a leader in the UDI, Borloo was not involved in the 2014 local elections, mentioning health reasons, such as frontal acute pneumonia and sepsis.

On 6 April 2014, Borloo announced in a letter to the executives of the UDI that he would resign immediately from "every political term and position" due to his health concerns.