Lenworth Johnson was born and raised in the St. John's City South constituency on Charlesworth Ross Street (formerly known as Nelson Street) to Wally and Ada May Johnson. He attended the Foundation Mixed School from 1960-1967. He obtained his Secondary education at the St. Joseph's Academy, where he excelled in academics and represented the Academy in basketball. After graduating from secondary school in 1973, he worked at the Bank of Nova Scotia, where he rose to the position of Assistant Manager of Operations in Grenada. Lenworth returned to Antigua in 1982 where he was employed as the Assistant Accountant at Joseph Dew, Division of Dantzler, West Indies.

He gained extensive experience in accounting between 1986 and 1993 and was part owner of the chartered accounting firm of Gregory and Associates. He is an experienced accountant and is a member of the Institute of Chartered Accountants of Antigua and Barbuda.

Mr. Johnson serves with distinction as a Senator in the Upper House of Parliament. He served both from 1989-1994 and was appointed once more in 2004. As Parliamentary Secretary in the Ministry of Finance and the Economy, Mr Johnson is part of the Ministry of Finance’s team which has revived the economy and re-established sound fiscal and monetary policies in Antigua & Barbuda.

He began studying law in 1993 at Holborn College in London, England. In 1996, he was awarded his Law Degree from the University of Wolverhampton in England. He completed his Certificate in Legal Education at the Hugh Wooding Law School in Trinidad. He was called to the Antigua & Barbuda Bar as an Attorney-at-Law in 1997.

He is currently the Treasurer of the United Progressive Party. He also serves as Chairman of both the St. John's Development Corporation and the Antigua and Barbuda Investment Authority. As head of these corporations he is in the forefront of guiding the progressive development of St John’s, attracting foreign direct investment to Antigua & Barbuda, and developing indigenous investment in the nation.