A school in Mayo and Microsoft offices also came out on top
The Royal College of Surgeons has been voted Ireland's favourite building.
A Mayo primary school and Microsoft offices are runners up in Public Choice category of the Royal Institute of the Architects of Ireland (RIAI) Irish Architecture Awards.
Number 26 York Street, the Royal College of Surgeons in Ireland, was the overall winner.
The new medical education building on the Dublin campus, which was designed by Henry J Lyons, fought off competition from a shortlist of 32 projects to claim the top prize.
It received 22% of the 10,000-plus votes cast.
The 10-storey, 10,000m2 building incorporates four basement levels to negotiate planning height restrictions in Dublin city centre.
The complex includes technically advanced simulated environments for clinical and surgical training, a new library, auditorium and sports facility.
It is the second win for Henry J Lyons and architect Peter McGovern, who also took the prize in 2010 for the Criminal Courts of Justice.
David Browne, RIAI president, said: "The winning project demonstrates the importance of investing in our educational sector and architects’ ability to deliver outstanding buildings in complex urban settings.
"This is the 10th year that members of the public have had an opportunity to vote on their favourite architectural project and the high number of votes cast demonstrates how passionate we as a nation are about the environments in which we live, work and relax.
"The shortlist was made up of exceptional projects including residential homes, commercial spaces, schools, healthcare facilities, heritage locations and public spaces and it’s encouraging that Irish people recognise the value that Irish architects add to all aspects of the built environment, supporting Ireland’s educational, economic and social infrastructure."
In second place was Scoil Phádraig, a primary school in Westport, Co Mayo designed by SJK Architects.
The design of the 16-classroom, 2,400m2 building is located alongside a church and creates a new public space and link to a pedestrian and cycle greenway.
Each of the 16 classrooms is a distinctive colour, while coloured window frames relate to the stained glass windows in the church.
Third prize went to One Microsoft Place - the tech giant's Dublin campus in Leopardstown - designed by RKD Architects.
The building has been designed in a mountain shape, reflecting the picturesque setting near the Dublin Mountains.