This paper is about an appeal against the judgment delivered by the Court in the first instance. The work is divided into ten units in which the appeal is more closely explained. After the introductory part of the work, which lists the general characteristics of the appeal as a fundamental human right guaranteed by the Constitution and international documents, follows a part in which is listed the deadline for appeal. Below we talk about people who are entitled to bring an appeal to the second-instance court. Further, it is described who and in what situations may waive the right to appeal, and also withdraw an appeal. In the heading entitled "content appeals" are listed all the ingredients that appeal must have so a higher court could act upon it. He also explained Institute beneficium novorum and the right to present new facts and evidence in the appeal. Then follow the grounds of appeal as the central and most important part of the work which is divided into four sections according to the specified grounds for appeal that are listed in the Criminal Procedure Act. Also the whole procedure that is carried out in relation to the complaint is described, as are all decisions that the appellate court brings while deciding on appeal. These decisions are further classified in the orders and judgments. Finally, it is concluded that the Croatian criminal procedural law gives sufficient procedural guarantees to all authorized persons to achieve their constitutionally guaranteed right to appeal against the judgment.