The ad uses the strapline "17.59. It's Guinness Time" which is designed to have a double meaning.
The beer was first brewed in Dublin in the year 1759, and 17.59pm is a key time for sales of the stout, according to the agency.
The ad was trailed on Facebook and will show during tonight's UEFA Champions' League match between Liverpool and Marseilles.
LONDON - Irish International BBDO has produced an ad celebrating 250 years of Guinness.