A tissue adhesive is described, which contains three separate components, i.e., a stabilized, essentially fibrinogen-free protein preparation that is of storage-quality in liquid state and contains the blood coagulation factor XIII a stabilized protein preparation that is of storage-quality in liquid state and contains fibrinogen. A chaotropic substance of less than 0.28 mol/liter was added to said protein preparation to avoid or reduce the aggregation of fibrinogen, and a preparation containing thrombin, which are provided in one packaging unit prepared to be used together. Furthermore, stabilized, frozen or lyophilized protein preparations containing fibrinogen and Factor XIII are described. Said protein preparations contain fibrinogen- and Factor XIII which remains stable for more than four weeks after defrosting or reconstitution, as well as one or more added chaotropic substances in a quantity of less than 0.28 mol/liter which prevents or reduces the aggregation of fibrinogen and contain inorganic salts of