"20 years ago today, we started shooting CLERKS. 20 years later, with no plan or provocation, I jumped out of bed at 4:20 this morning and started writing CLERKS III," Smith wrote on his Facebook page.
"It's been like hanging out with old friends. And after 2 hours of tapping the keys and giggling, I have come to a conclusion... CLERKS III will be the best film I'll ever make."
No start date on the project was specified.
Smith, 42, began his career with the independent film "Clerks." He followed that up with "Dogma," "Chasing Amy" and "Clerks 2," as well as "Mallrats," "Jersey Girl" and "Jay and Silent Bob Strike Back."
Notable deaths of 2014 [PHOTOS]
James Wan tapped to direct 'The Conjuring 2'