The changes have left many asking questions about his motive.
Sierra Leone’s Foreign minister Samura Kamara has relinquished the docket to concentrate on pursuing the presidency.
Mr Kamara was last month named the flagbearer of the ruling All People’s Congress (APC) party in next year’s election.
His replacement was among the numerous changes in the Cabinet made by President Ernest Bai Koroma on Monday, just about three months before a presidential election.
The changes have left many asking questions about the president's motive.
Mr Kamara was replaced by former Central Bank Governor Kaifala Marah, according to a presidential statement.
Mr Marah was among about a dozen candidates who contested the APC’s presidential ticket. He had to resign as the bank boss in line with constitutional provisions.
The latest Cabinet changes also saw Major (Rtd) Alfred Palo Conteh appointed the new Defence minister.
Major Conteh previously served as Internal Affairs minister. The Defence portfolio had been vacant since the beginning of President Koroma’s second term after the 2012 polls.
President Koroma also made changes in the ministries of Information, Finance and Social Welfare.
Former presidential adviser Alpha Kanu was appointed Information minister, replacing Mohamed Bangura – the man who succeeded him in the same office in 2013.
Mr Bangura was one of two presidential advisers named on Monday. Others include two other former APC presidential flagbearer contestants.
The changes on Monday came less than a week after a major shakeup in the top security echelon, hence the questions about the president's motive.
While some say the rehiring of former ministers made no sense, with less than four months to the end of President Koroma's mandate, others say it was a strategic move of calming tension sparked by his decision to hand-pick the party's presidential candidate.