Jonathan Walker came from Newcastle-on-Tyne to run the marathon for the Hearing Dogs for Deaf People charity.
After doing the London marathon, he didn't know what to expect in Dublin.
"It's slightly more hilly, I have to say, but it was really friendly with loads of encouragement the whole way around. I really enjoyed it."
His brown floppy ears brought lots of cheers from the public.
"I wasn't sure if it was a good idea at the start but there was a lot of encouragement all the way around with calls of 'go on, you ears'."
