The document, conducted by the country's Central Statistics Office (CSO), will be used for a wide range of purposes, including the development of public services.
It is also regarded as an important historical record, coming 100 years after the Rising.
Enumerators will begin delivering census forms on Thursday.
Launched by Taoiseach (Irish prime minister) Enda Kenny, the census will be unchanged from the last one carried out five years ago, other than one question recognising the legal status of same sex marriages.
The CSO says that because of the recession, there was no budget available to carry out a public consultation, which may have resulted in new questions.
The last census in 2011 recorded the population as 4,588,252.
The new census will show the net increase or decrease in population over five years.
A senior statistician with the office said every person in the Republic of Ireland on 24 April must, by law, be entered on a census form.
PÃ¡draig Dalton, Director General of the CSO, noted the extent of the work involved in making the census happen.
"Counting every single person in the state on a single night is no easy task," he said.
"As you can imagine, an enormous amount of work has already gone into this census to get us here today."
Mr Dalton described it as "a traditional census" in which forms will be delivered by hand to every household in the country over the next five weeks, and then collected in person.
Traveller rights group Pavee Point has published an information section for travellers and members of the Roma community on its website.
An information video in the Romani language is available on the website to encourage Roma people to complete the form and mark their ethnic group.
A traveller specific video and information leaflet has also been produced.
The last Census in 2011 registered approximately 26,000 travellers, whereas the All Ireland Traveller Health Study carried out in 2010 by traveller researchers registered 36,000 travellers in the Republic.
A census is to be carried out in Republic of Ireland on 24 April - the anniversary of the 1916 Easter Rising.