In 1989, Mr. Maithripala Sirisena, for the first time contested in the general elections from the Polonnaruwa District and became a Member of Parliament (MP) on 15th February 1989. He contested under the well-known SLFP symbol “HAND” and this was the last time this symbol was used in an election in Sri Lanka.
In the general elections of 1994, he obtained the highest number of preferential votes from Polonnaruwa District. After this, he was made the Deputy Minister for Irrigation.
In 1997 he was offered the Cabinet Ministerial portfolio of Mahaweli Development and Parliamentary Affairs and was elected as the General Secretary of the SLFP in 2001.
In 2004 he was also appointed as the Leader of the House of Parliament.
In 2005 he was given the portfolios of the Cabinet Minister of Agriculture, Irrigation and Mahaweli Development and the Minister of Environment & Natural Resources.
In 2007, following the cabinet reshuffle he was appointed as the Cabinet Minister for Agricultural Development and Agrarian Services Development.
Since 2005 at the height of the war in Sri Lanka, Minister Maithripala Sirisena functioned as the Acting Defence Minister of Sri Lanka on nine occasions. He was the acting Defence Minister in the final days of the war in Sri Lanka in the absence of the Defence Minister, the then President.
Minister Maithripala was elected once again to the parliament in 2010 and was appointed as the Cabinet Minister of Health of the UPFA government.
At the Presidential Election held on 8th January 2015, he was elected as the 6th Executive President of Sri Lanka.