Purpose of this paper is to present traits of penal law during Stalinist period in Poland based on a handbook by I. Andrejew, L. Lernell and J. Sawicki “Prawo karne Polski Ludowej”, which was first published in 1950. For this purpose, a number of issues appearing in the publication were described, such as: materialist definition of crime, ex post facto law, penality of preparation, attitude towards pre-war legislation instituted by interpretation, criticism of sociological school in penal law, position of death penalty in punishment system. Based on characteristics of them, traits of Stalinist penal law were identified, some of which are: excessive repressiveness, subordination of law to the power, or its instrumentalization. Identification of these traits was made possible by utilization of modern literature concerning the subject, presentation of regulations from laws having effect at the time, as well as comparison of handbook’s contents with current historical knowledge. Characteristics of traits of Stalinist penal law was preceded by a description of circumstances of origins of the handbook – its position among existing course books, reviews and consideration of impact of authors’ personal background on character of their work. What is more, teaching of penal law in the early days of Peoples’ Poland was briefly described, with an indication, why work of I. Andrejew, L. Lernell and J. Sawicki was particularly needed in law schools created by communist government.