The Devils are 47-24-8 and have 102 points -- tied for the second-most in the NHL Eastern Conference -- with three games left in the regular season.
The team gave no reason for the change on its Web site announcement.
Lamoriello also took over the team in December of the 2005-06 season, guiding the Devils to a 32-14-4 record and Atlantic Division title. New Jersey won its first playoff series last year but lost in the second round.
He also fired a coach with eight games left in the 1999-2000 season with the team in first place. The Devils ended up winning the Stanley Cup behind Lamoriello that year.