Banharn made a fortune in the construction business before he became a Member of Parliament representing his home province of Suphan Buri.

[6] Banharn's construction company was very successful in the 1960s, when large sums were invested in major infrastructure projects, including military facilities.

[6] Banharn Silpa-archa was persuaded to enter politics by Booneua Prasertsuwan, a veteran member of the House of Representatives.

[7] In 1976, Banharn Silpa-archa made his political debut when he was elected a Member of Parliament, representing Suphan Buri Province.

The local press has once dubbed him "Mr. (Mobile) ATM" (automated teller machine), due to the suspicion that he had bought the loyalty of political associates in exchange for money.

Banharn returned to the cabinet as early as April 1992, when he once again became Minister of Transport in the short-lived government of General Suchinda Kraprayoon.

[4] Under the leadership of Banharn, the Thai Nation Party won the parliamentary election in 1995, and he became the 21st Prime Minister of Thailand, leading a seven-party coalition.

Due to his earlier vow before the Emerald Buddha never to rejoin Thaksin because of the corruption scandals, this move reinforced Banharn's image as a "slippery eel".

[10] Upon the dissolution of his Thai Nation Party by the Constitutional Court on 2 December 2008, Banharn Silpa-archa was banned from politics for five years.