They asked participants to help set a new Guinness World Record for the largest gathering of people wearing false mustaches and said 1,408 people did so Thursday evening.
The record awaits Guinness certification.
Gilda's LaughFest said participants who came to Rosa Parks Circle in downtown Grand Rapids received official LaughFest mustaches.
According to LaughFest officials, the current fake mustache world record of 648 participants was set in September 2012 at an event organized by the St. Louis Rams.
Last year, LaughFest's kickoff event broke a Guinness World Record for the largest number of people wearing fake animal noses. The year before that it was people tossing rubber chickens.
LaughFest began Thursday and runs through March 17.