Sudden cardiac arrest refers to a sudden and unexpected stoppage of the heart. In Croatia, this alarming event claims one life every hour, or a total of 24 people per day. Knowing the basic guidelines for life support and the application of cardiopulmonary resuscitation can give an injured individual a chance for survival. Applying cardiopulmonary resuscitation actually "buys" time until emergency medical help arrives. The establishment of normal heart function and the prevention of cardiac arrhythmias are achieved by an electric shock delivered by an automated external defibrillator (AED). These portable devices are easy to use and can be safely operated by laypersons, ultimately saving lives by administering a controlled electric shock. Research shows that only 1 % of the general population is able to effectively perform basic life support measures; however, if 15-20 % of the population were trained to provide adequate first aid, the mortality rate in outpatient settings would significantly decrease. Due to the devastating results in the general population, this research aimed to assess the knowledge and attitudes of undergraduate nursing students at the University of the North about cardiopulmonary resuscitation and the use of AED. The research was conducted using the "Google Forms" questionnaire from June 6 to August 20, 2024. 115 participants took part in the research. The first part of the questionnaire contained socio-demographic questions and basic questions about education. The second part of the questionnaire examined the knowledge and attitudes of undergraduate nursing students at the University North about cardiopulmonary resuscitation and the use of AED. Before conducting the statistical analysis, three hypotheses were put forward: there is a statistically significant difference in knowledge and attitudes about cardiopulmonary resuscitation and the use of AED between students with a completed five-year medical level of high school education compared to students with other levels of high school education at the University North, there is a statistically significant the difference in knowledge and attitudes about cardiopulmonary resuscitation and the use of AED between students in different years of undergraduate nursing studies at the University North and there is a statistically significant difference in the knowledge and attitudes about cardiopulmonary resuscitation and the use of AED between older and younger undergraduate nursing students at the University North. In the paper, the first hypothesis was accepted, while the second and third were rejected. The research was compared with the results of research from other members of the European Union and the United States of America. The results of the research showed that there are more undergraduate nursing students of the University North who have satisfactory knowledge and attitudes for providing cardiopulmonary resuscitation and using AED devices than those who do not. Despite this, it should be emphasized that the shortcoming of this research work is the too small sample of survey participants, and the results cannot be generalized.