Else "Els" Borst-Eilers (Dutch pronunciation: [ˈɛlsə ˈʔɛls ˈbɔrst ˈɛilərs]; 22 March 1932 – 8 February 2014) was a Dutch politician of the Democrats 66 (D66) party and physician. She was granted the honorary title of Minister of State on 21 December 2012.

Borst worked as a medical researcher at the Academic Medical Center from 1958 until 1962 and as a physician from 1962 until 1976. Borst also worked as director of the blood bank at the University Medical Center Utrecht from 1969 until 1976. She served as the University Medical Center Utrecht hospital administrator from 1976 until 1985. Borst was selected as Vice Chairwoman of the Health Council, serving from 1 January 1986 until 22 August 1994. Borst also served as a professor of medical ethics at the University of Amsterdam from 1 July 1992 until 22 August 1994. After the election of 1994 Borst was appointed as Minister of Health, Welfare and Sport in the Cabinet Kok I, taking office on 3 August 1998. After the Leader of the Democrats 66 Hans van Mierlo announced he was stepping down five months before the election of 1998, he endorsed Borst as his successor. After Van Mierlo stood down on 15 February 1998, Borst was chosen to succeed him and became the Leader of the Democrats 66 and the Lijsttrekker (top candidate) of the Democrats 66 for the election of 1998. The Democrats 66 suffered a small big loss, losing 10 seats and now had 14 seats in the House of Representatives. Borst was elected as a Member of the House of Representatives and became the Parliamentary leader of the Democrats 66 in the House of Representatives on 19 May 1998. Borst stepped down as Leader of the Democrats 66 and Parliamentary leader in the House of Representatives in favor of Thom de Graaf on 30 May 1998. The following cabinet formation resulted in a continuing coalition agreement between the Labour Party (PvdA) and the People's Party for Freedom and Democracy (VVD) to form a Cabinet Kok II with Borst continuing as Minister of Health, Welfare and Sport and also becoming Deputy Prime Minister, taking office on 3 August 1998. In 2001 Borst announced her retirement from national politics and that she would not stand for the election of 2002.

Following her retirement Borst occupied numerous seats as a nonprofit director for supervisory boards for non-governmental organizations (Dutch Cancer Society, Netherlands Cancer Institute, Helen Dowling Institute, Institute for Health Services Research, National Committee for 4 and 5 May and the Brain Foundation) and as an advocate for cancer research. Borst continued to comment on political affairs as a stateswoman until her death on 8 February 2014 when she was murdered by a mentally unstable man in her home.