Background This study aimed to determine the cardiopulmonary resuscitation (CPR) knowledge level and factors affecting the current CPR knowledge level among EMTs and paramedics working in the Kayseri 112 emergency health system. Methods This survey aimed to reach all paramedics and emergency medical technicians working in the 112 emergency health system in Kayseri province. The data collection consists of sociodemographic/occupational characteristics, CPR training and practice characteristics and 20 four-choice CPR knowledge questions. Multiple linear regression analysis was used to determine the independent variables that affect the number of correct answers given to the questionnaire. Results 305 healthcare professionals were included in this study. 57.0% (n = 174) of the participants were female and 56.1% were under the age of 30. It was found that 65.6% (n = 200) of the healthcare professionals were EMTs, and 48.6% (n = 148) had been working for 6–10 years. The mean number of correct responses based on the 20 questions asked was 12.76 ± 3.11. In multivariable analysis, it was determined that having received training on CPR after 2015, having participated in a course or seminar on CPR in the last 3 months and having practiced defibrillation/cardioversion during CPR significantly increased the level of knowledge regarding CPR (respectively, p < 0.01, p = 0.025, p = 0.045). Conclusion CPR trainings, which have been received recently and based on the current guidelines, increase the level of CPR knowledge and the increasing knowledge level affects the use of defibrillation/cardioversion. Improving training increases knowledge and practice.