Slice, which is part of Engine, will be handling ongoing PR for the brand and is charged with raising awareness of the brand among consumers.
Kerrygold is owned by a co-operative of Irish dairy farmers.
The team will be led by Slice creative director Miranda Mitchell and senior account director Xenia Xenophontos. They will report to Kerrygold marketing controller Alison Palmer.
Slice MD Nadia Gabbie said of the appointment: 'Kerrygold is an exciting new win for us as an agency as it sees us branching into food PR, which we see as a promising area of growth for Slice.'