Background <p>Cardiopulmonary cerebral resuscitation is the first-line treatment for cardiopulmonary arrest, documented as one of the most common medical emergencies and the leading causes of death globally. The aim of this study was to investigate the effects of the personalized video feedback of Basic Cardiac Life Support (BCLS) on knowledge and skill levels among undergraduate nursing students.</p> Methods <p>This randomized controlled trial was conducted at a nursing school in Tehran, Iran, in 2023. Forty incoming students were chosen through the census method and divided into experimental and control groups by simple randomization. The students of both groups were taught about BCLS through lectures and simulation-based techniques in two 120-minute sessions. Then, the students performed BCLS on the mannequin and recorded it with a digital camera, then immediate personalized feedback was given in both groups. Next, the recorded video with personalized feedback from the experimental group was made available to them that it was the only difference between the two groups. One week and one month after retraining, the BCLS knowledge and skills levels of both groups were examined. To collect the data, the personal profile form, the BCLS knowledge questionnaire, and the BCLS skills Checklist were utilized.</p> Results <p>There was no significant difference in the individual characteristics (<i>p</i> &gt; 0.05) and the mean scores of BCLS knowledge (<i>p</i> = 0.762) and skills (<i>p</i> = 0.715) in both groups before training. There was no significant difference in the mean scores of BCLS knowledge in both groups immediately (<i>p</i> = 0.467), one week (<i>p</i> = 0.904), and one month (<i>p</i> = 0.626) after training. No significant difference was observed in the mean scores of BCLS skills in both groups immediately after training (<i>p</i> = 0.303), while one week (<i>p</i> &lt; 0.0001) and one month (<i>p</i> &lt; 0.0001) later, the mean skills scores in the experimental group were higher than those in the control group.</p> Conclusions <p>Providing feedback to students via personalized video appears to have a greater impact on students’ knowledge and skills regarding BCLS than providing in-person feedback alone. So, it was recommended to apply this student-centered and self-directed training in undergraduate nursing students after more studies in larger groups.</p> Trial registration <p>The study has been registered in the Iranian Registry of Clinical Trials (No. IRCT20230911059402N1, Date: 12/10/2023).</p>