Artist Warren Elsmore led a team, which included volunteers, in building the 6ft 6in (2m) version of the piece known as the Berserker.
The Lego model will be on display at the National Museum of Scotland in Edinburgh until 24 March.
The chessmen are thought to have been made in Scandinavia, possibly Norway, in about AD1150-1200.
The 93 figures were found buried in a sand dune near Uig on the west coast of Lewis in the 1800s.
One of the historic Lewis Chessmen has been recreated on a larger scale using more than 90,000 Lego bricks.