Mangala Pinsiri Samaraweera (Sinhala: මංගල පින්සිරි සමරවීර, Tamil: மங்கள சமரவீர; pronounced [mˈʌŋgɘlɘ pinsiri sˈʌmɘrɘviːrɘ] 21 April 1956 – 24 August 2021) was a Sri Lankan politician. He was the first openly gay politician in Sri Lanka. He served as Minister of Finance from 2017 to 2019, and as the Minister of Foreign Affairs, for two terms from 2005 to 2007 and 2015 to 2017. He created a stir in Sri Lankan politics when he was sacked as a minister by President Mahinda Rajapaksa in 2007, after which he split from the Sri Lanka Freedom Party to form his own wing (Mahajana wing), which later merged with the United National Party in 2010.

Samaraweera served as a politician for over 30 years in his career until his retirement from politics in 2020. During his tenure as a politician, he was an advocate of liberalism and radical centrism and opposed militarisation, as well as ethnic and religious polarisation. He also advocated for LGBTQ rights in Sri Lanka, despite same-sex sexual activity and same-sex marriage being illegal in Sri Lanka.

Mangala Samaraweera was born on 21 April 1956 in Matara, Sri Lanka, the son of Mahanama Samaraweera and Khema Padmawathi Amaraweera. His father was a cabinet Minister of Local Government, Housing, Communications, Posts and Telecommunications in Sirimavo Bandaranaike's government and his mother served as a member of the Matara Urban Council.

After schooling at Rahula College Matara, Nalanda College, Colombo and Royal College, Colombo, at Waltham Forest College, London he gained a BA in Clothing Design and Technology from St. Martin's School of Art in London, he served as a design consultant to the National Design Center of Sri Lanka and served as a visiting lecturer in the Institute of Aesthetic Studies, University of Kelaniya. Veteran textile designer Chandra Thneuwera invited him to join her at the Institute of Aesthetic Studies while he was working as a consultant for the Ministry of Textile Industries under the guidance of Wijayapala Mendis.

Samaraweera entered politics from the Sri Lanka Freedom Party as its chief organiser in Matara in 1983. He was introduced as Khema's boy when he was appointed as SLFP's chief organiser. He later became the SLFP party's Assistant Secretary and Coordinating Secretary of the Mother's Front. He also served as human rights campaigner in the 1980s when Ranasinghe Premadasa was the president of Sri Lanka.

He first entered the Parliament of Sri Lanka as a representative of the Matara District in 1989, and he was appointed Minister of Post and Telecommunications in the cabinet of President Chandrika Bandaranaike Kumaratunga in 1994. He also served as the Minister of Urban Development, Construction and Public Utilities in the same Cabinet after a reshuffle and was later given the Deputy Minister of Finance portfolio.

Following the election defeat of his party in 2001, he was made the Chief Opposition Whip and the Treasurer of the Sri Lanka Freedom Party. In 2004 he became the Minister of Ports, Aviation and Media in the new cabinet of President Chandrika Bandaranaike Kumaratunga.

In June 2005, after conflicts with Kumaratunga, he dropped the Media Ministry, but remained Cabinet Minister of Ports and Aviation. He became the campaign manager for Presidential candidate and Prime Minister Mahinda Rajapakse. When Rajapakse won and took office in November 2005, he surprised many by appointing Samaraweera to the additional post of Foreign Minister instead of Prime Minister; Samaraweera maintained his other posts.