Pearce was born in East London, and brought up in Dagenham, England. At the age of fifteen he joined the National Front (NF), a far-right political party opposed to a multi-racial and multi-cultural England. He was closely involved in NF organisational activities and first came to prominence in 1977 when, at the age of sixteen, he set up Bulldog, the paper of the organization. Bulldog became associated with some of the most virulent NF propaganda and Pearce was twice convicted under the Race Relations Act of 1976, serving time in prison in 1982 and 1985—1986. In 1980 Pearce became editor of Nationalism Today, in which he argued vehemently in favour of racial preservation, producing a pamphlet entitled Fight for Freedom! on this theme in 1982. He was a frequent visitor to Northern Ireland and he maintained regular contact with the Ulster Defence Association

Pearce attributes his subsequent religious conversion from a culturally-Protestant agnosticism to Roman Catholicism in part to reading G. K. Chesterton, whose biography he later wrote. He now repudiates his former views, saying that his racism stemmed from hatred, and that his conversion has completely changed his outlook.

As a Catholic author, he has focused mainly on the work of Catholic English writers, such as Chesterton and Hilaire Belloc. His book Literary Converts, published in 1999, captures this interest and showcases the process of conversion of many writers who became convinced Catholics. Pearce has also promoted the social doctrine of the Church, in particular Distributism as a Catholic economic system. His main contribution in this area has been his book Small is Still Beautiful, which takes up the theme proposed earlier by E. F. Schumacher in his book Small is Beautiful.

Joseph Pearce is the host of the EWTN television series The Quest for Shakespeare based on his book The Quest for Shakespeare: The Bard of Avon and the Church of Rome. The show concentrates on the evidence that Shakespeare was a Catholic and consists of thirteen episodes.