John McDermott claimed the English heavyweight title on a unanimous decision against Matt Skelton at the York Hall in Bethnal Green.
McDermott was given the verdict in the 10-round contest for the vacant belt by margins of 97-93, 97-94 and 97-94.
The 33-year-old, fighting for the first time in over a year, improved his career record to 28-8 and settled an old score with Skelton, who won inside the first round when they met previously in 2005.
This is McDermott's second spell as English heavyweight champion. He held the belt from April 2008 to September 2009, when he lost it on points to Tyson Fury.
Skelton, 46, also now has a 28-8 career record but has lost his last two fights.
The former world-title challenger was knocked out in two rounds by David Price last November.