There were over 8,500 fewer blood donations in the first ten months of this year compared to the same period in 2019.
Donations have dropped by 33% in three counties.
These new figures have been released by the Irish Blood Transfusion Service under the Freedom of Information Act.
They show that, in the first ten months of 2019, there were 112,218 blood donations throughout the country.
In the same period this year, there were only 103,714 - a decrease of nearly 8%.
Paul McKinney, operation director for the Irish Blood Transfusion Service, says there was a sharp drop earlier this year due to COVID-19.
He said: "It really happened from the 16th March onwards, for a five-week period - obviously from when lockdown was first brought in.
"We had an average over that five-week period of 33% decline in the number of blood units we issued to the hospitals."
18 counties have had a drop in donations this year.
They've dropped by a third in Kerry, Laois and Offaly, and by 28% in Donegal.