Fáilte Ireland says the Wild Atlantic Way is one of its top priorities for 2014.
The agency will spend €8m this year on marketing the route, which stretches from Donegal to West Cork.
Failte Ireland says 98% of those providing accommodation for tourists expect 2014 to be good.
CEO Shaun Quinn said the Wild Atlantic Way resonates with potential tourists much more than individual counties.
"Going abroad and promoting Mayo or Clare or Kerry doesn't mean anything" he said. But the Atlantic coast conjures up an image in the mind."
He said the investment from the Government would go towards the final completion of the route, including full signposting which will be completed by March.