Born in Lausanne, he studied literature at the University of Lausanne and was president of the Swiss Students' Association. He taught French, history and geography in the secondary schools of Préverenges and Lausanne, and was also from 2000 to 2004 the regional secretary of the trade union FTMH Vaud Fribourg.
In politics, he served in the municipal parliament of Lausanne from 1990 to 1998, in the Grand Council of Vaud from 1998 to 2000 and in the National Council from 1999 to 2004. There, he was a member of the committees responsible for the environment, for land use planning and energy, and for finance.
Since 1 December 2004, he is a member of the Council of State of Vaud and head of the Department of Health and Social Services. In March 2011, he became the first Socialist politician in the history of the canton of Vaud to be elected in the first round of a popular election, with 54% of votes cast. From March 2004 to 2008, he was also vice president of the Social Democratic Party of Switzerland.
On 26 October 2011, he announced his candidacy to succeed Federal Councillor Micheline Calmy-Rey. On 25 November 2011, the parliamentary group of his party chose him, together with Alain Berset, as one of the party's candidates for the election of 14 December 2011.
- "DSAS: Chef du département". Canton of Vaud. Retrieved 14 December 2011.
- Biography of Pierre-Yves Maillard on the website of the Swiss Parliament.
- « Pierre-Yves Maillard se lance dans la course au Conseil fédéral alors que Jean Studer renonce », tsrinfo.ch, 26 October 2011
- «Le PS met ses espoirs dans un duo de ténors », Le Temps, 26 November 2011.
- (in French) Yelmarc Roulet and Skjellaug Aïna, "« J’invite le parti de l’économie à travailler avec la gauche »", Le Temps, Friday 4 December 2015 (page visited on 4 December 2015).