Republic of Serbia has bilateral treaties on legal assistance in civil matters with 15 EU Member States. Many years have passed since the conclusion of all these treaties and significant changes have occurred in the area of Private International Law. In the first place, these changes result from the accession of the Republic of Serbia to certain Conventions of the Hague Conference on Private International Law, development of the EU Private International Law, but also the drafting of new Private International Law Act of the Republic of Serbia. This is why the provisions of bilateral treaties, especially provisions on conflict of laws and international jurisdiction, are not harmonised. In addition, there are several parallel systems of legal norms in the area of Private International Law which apply depending on whether a multilateral treaty, bilateral treaty or national law is in force with the state in question. This situation is causing confusion not only among persons whose relations are regulated by the norms, but also among practitioners (judges and attorneys at law) who have great difficulties in determining which law to apply in a particular case. All this creates legal uncertainty and erroneous application of substantive law, which is one of the grounds on which a judgment may be set aside. In order to solve these problems, competent institutions of the Republic of Serbia should extensively analyse existing bilateral treaties on legal assistance in civil matters with EU Member States and take all necessary steps towards their revision as soon as possible, but certainly before the adoption of the PIL Act of the Republic of Serbia.