Aho was born in Veteli, Finland. Prior to attending university, he began a career in politics. From 1974 to 1979, he was Chairman of the Finnish Centre Youth, which had before him grown many of his predecessors to high political situations. In 1978, he became a Presidential elector, a position he also held in 1982 and 1998. From 1979 to 1980, Aho was Political Secretary to the Ministry of Foreign Affairs. From 1980 to 1983, he was a trade promoter for the Kannus municipality.
Aho studied at the Helsingin yliopisto (University of Helsinki), receiving a Master of Social Science degree in 1981.
Since 2010 he has been a Skolkovo Foundation Council member.
Aho was first elected to the eduskunta (Finnish Parliament) in 1983. He became Chairman of the Centre Party in 1990, a position that he held until 2002. The party is one of three major political parties in Finland.
At 36 years of age, he was the youngest Prime Minister in Finnish history.
Aho was the prime minister of the centre-right coalition government (Centre Party, National Coalition Party, Christian Democrats and Swedish People's Party) from 1991 to 1995. He is best known for leading Finland into the European Union. Aho's own party, gaining most of its support from rural areas, was the most opposed to EU membership among major parties. Their greatest concern was the agricultural situation, but they were persuaded to support membership due to the prime minister's diplomacy. Finland applied for EU membership on 16 March 1992 and a referendum was held two and a half years later. Aho's government faced also the deep economic depression of the early 1990s. Despite a steep rise in the national debt, the Aho government applied a stringent cut-and-save policy that made it unpopular. This partly caused its fall in the 1995 election and Centre Party's eight-year period in opposition.
He was known by the nickname "Kannuksen Kennedy" ("The Kennedy of Kannus", Kannus being his hometown) due to his streamlined and well coiffed habitus, a comparison with United States President John F. Kennedy.
Esko Aho lost the bid for President of Finland to Tarja Halonen in 2000. After that he retired from active politics in the early initially through a "sabbatical leave" of one year to lecture at Harvard University (where he was resident fellow at the Institute of Politics). In the 2003 election he left parliament and retired from daily politics. He then served as the president of the SITRA, the Finnish National Fund for Research and Development (the state innovation fund).
In 2008, Aho's name was included in an opinion poll of possible Presidential candidate, which he ranked last.
It was announced by Nokia in August 2008 that Aho would be joining Nokia as Executive Vice President of Corporate Relations and Responsibility and become a member of its executive board. He took up these positions on November 1, 2008.
At the time of his rise to Prime Minister, he was the youngest head-of-government in Europe.Aho Cabinet