Background: Acute coronary syndromes compose a major proportion of sudden deaths globally.Patients diagnosed with myocardial infarction due to sudden chest pain should be immediately referredto percutaneous coronary angiography (PTCA) as soon as possible. In order to decrease the mortalityrate due to acute coronary syndromes and deadly cardiac arrhythmias, the electrocardiography (ECG)knowledge of the ambulance staff, who evaluated as first, is important. We aimed to evaluate the levelof electrocardiography knowledge by conducting a survey on the ambulance staff in the province ofSivas.Material-methods: A total of one hundred seventy-eight healthcare professionals working inambulances in the centre and districts of Sivas were included in the study, including nurses, paramedics,and emergency medical technicians. The participants were asked to answer survey questions abouttheir working experience, education, age, and completion of a special ECG course and they wereexpected to interpret 12 different ECGs.Results: The ratios of correct ECG diagnosis were as follows; anterior ST-elevation myocardial infarction(STEMI), 84.3% (n=150); inferior STEMI, 89.9% (n=160); lateral STEMI, 77.5% (n=138); normal ECG, 64%(n=114); ventricular fibrillation (VF) , 28.1% (n=50); supraventricular tachycardia (SVT), 57.3% (n=102);VT, 17.4% (n=31); and artificial ECG, 13.5% (n=24). According to the results, paramedics had highercorrect diagnosis ratios in right bundle branch block and AV complete block compared to EMTs andnurses (<0,001), and EMTs were better in correctly diagnosing left ventricular hypertrophy (p=0,011).Conclusion: In our study, it was shown that profession, working experience and status of ECG educationin the recent year did not make a significant difference, also it has been shown that employees donot recognize life-threatening rhythms on ECG assessment results, suggesting to revise the in-servicetraining.