An administrative dispute is a form of judicial control over the administration. It is regulated by the Law on Administrative Disputes. This paper defines an administrative dispute and the subject of an administrative dispute. Furthermore, we analyze administrative courts, their organization, jurisdiction and composition. In addition to the mentioned, the changes introduced by the new Law on Administrative Disputes compared to the previously valid law are emphasized. The further focus of the paper is on the first-instance administrative dispute: the court's actions on the claim in the first-instance administrative dispute. After submitting the lawsuit to the court, the court assesses the jurisdiction, regularity of the lawsuit and the prerequisites for conducting an administrative dispute. The paper describes the courts decisions on the claim and the factual situation with the obligation to deliver the claim to the defendant and the interested person for a response. The paper also states the rights and obligations of all the parties to the dispute, as well as the obligation to submit documents available to public law bodies. Finally, we emphasize the importance of an oral hearing and the resolution of an administrative dispute without a hearing.