Fresh frozen plasma (FFP) is one of the most frequently used blood components. Its use is continuously increasing, although 50 to 80% of units are not used according to the approved indications. The quality control of FFP was performed in 6 blood transfusion centers. The volume of FFP unit was between 178 and 234 ml. F VIII: C above 0.70 i. u./ml was observed in 40.9 of units. Plasma in 0.9% of units was not sterile and the concentration of total proteins and hemoglobin were within the acceptable range.