Just six per cent of people in Northern Ireland who could donate blood do so.
Health Minister Michael McGimpsey led from the front by donating blood as he encouraged the other 94% to consider following suit.
The blood Transfusion Service is looking to recruit 9,000 new donors this year.
There is a heightened need for donors in the months ahead because those who regularly give will be ruled out if they are among those affected by the anticipated surge in swine flu in the autumn and winter.
Mr McGimpsey said: "Blood donation is vital for the delivery of health care, saving and enhancing lives. We all know someone who has benefited from donated blood through emergency surgery, for routine operations, in the treatment of cancer or childbirth."
Around 500 patients in Northern Ireland need life saving blood every week and 300 people a day are needed to provide it to meet demand, he said.
The minister added: "There is of course a heightened importance for people to donate blood ahead of an anticipated surge in swine flu cases in the autumn and winter. This would rule out normally healthy regular donors who would not be eligible to donate until fully recovered from the illness."
He said: "With an increasing demand for blood and only 6% of Northern Ireland's population currently donating, that leaves 94% of the eligible population that does not donate.
"I would urge all eligible people across the province to consider becoming a blood donor."