The final footfall figure for 2012 was 1,029,417, up from 2011's 1,005,776 visitors.
Leo Oosterweghel, Director of Dublin Zoo, said: "We are absolutely thrilled to have welcomed even more visitors than last year. We would like to thank all our friends and supporters, old and new, who helped us achieve this new record. Reaching one million in 2011 was fantastic, but to do it again and add to that number is phenomenal.
"Our success can be attributed to the dedication and hard work of the team at Dublin Zoo. The team continuously strives to enhance the animal habitats and at the same time ensuring that visitors have an unforgettable experience which is value for money.
"We are delighted to say that the Zoo is more popular than ever. We are extremely proud to be in a position to say that after a decade of continuous development that Dublin Zoo is amongst the best zoos in the world.
"The Zoo belongs to the Irish people who have a great pride in such a world-class facility and we share our success with the generations who continue to support us."
For more on Dublin Zoo, visit: www.dublinzoo.ie.