The Blood Bank's reserves are down to a criticial level, the bank said in an urgent appeal for blood.
It said all types of blood were needed but especially O positive.
The bank, which is adjacent to St Luke's Hospital in Guardamangia, is open all week from 8am to 6pm. Blood can also be donated at Mater Dei Hospitals near the brown wards on Mondays between 2 and 7pm or at the Gozo hospital Mondays to Saturdays between 8.30 and 11.30am.
Donors have to produce their ID card or a driving licence.