Reenan, who reports to managing director Billy O'Regan, has been at Green Isle for more than five years, joining from Kraft Foods as brand manager and holding subsequent posts as buyer and marketing manager.
Former Guinness marketer Andy Kinsella was appointed to the job in March 2001 but only stayed a year before leaving without a job to go to. In the interim, non-executive director Michael O'Rourke has overseen marketing.
He retains the title of non-executive marketing director.
Goodfella's launched a £5m television, poster and print campaign in October through Leith London, aimed at positioning the brand as an alternative to Italian restaurant fare. Leith was hired to the account in April.