The two-component tissue adhesive system where the one component is a concentrated human fibrinogen solution and the other component is a thrombin solution containing Ca2+ is becoming increasingly important in surgery. In the commercially available tissue adhesive, the fibrinogen is separated from pooled plasma. The risk of transmitting foreign immunogens and viruses, always present when foreign biological materials are used, will be eliminated if the fibrinogen is separated from the patient’s own blood. A method using ethanol precipitation is described for preparing a concentrated fibrinogen solution from plasma separated from small amounts of blood. The method is fast, the final product can be obtained within 30–60 min after collection of the blood. The recovery is compared with the recovery obtained by separating the fibrinogen with ammonium sulfate precipitation and with cryoprecipitation. The method using ethanol is by far the most profitable, and the product is evaluated by experimental liver surgery in p