Abstract: The aim of this study was to compare the effect of a 40:2, 15:2 versus 30:2 Compression: Ventilation (C: V) ratio on rate of Chest Compression (CC), rescuer fatigue and satisfaction. We measured the BP and pulse. Fifty three persons performed BLS and CPR using C: V of 15:2, 30:2 and 40:2 on an adult resuscitation lardal manikin for 2 min. Two researchers measured the above mentioned variables. Data were analyzed by ANOVA, student's t-test or Mann-Whitney U test between groups. The value of p<0.05 was considered as significant. The results revealed fatigue after 2 min and satisfaction from the performed technique in the groups differed (p<0.05). Number of breathing in two minutes was 8.8±4.7(1-24). Total cardiac massage in 2 min. in the study groups was 131.7±40.6 (20-265), of this number in130.6±40.5 was done correctly. The number of compression per 2 min increased with C: V ratio of 40:2 than to other C: V ratio. Most of participants (71.7%) prefer using 30:2 ratios to achieve the primary goal of Cardiopulmonary Resuscitation (CPR). The PR and systolic, diastolic BP of rescuers before and 2 min after resuscitation had insignificant difference (p<0.001) and SBP differed between groups (p<0.04). Although the rescuers prefer to perform the C: V ratio 30:2, but number of CC is less than standard recommended by AHA. Alternative C: V ratio of 40:2 methods, is equal to the AHA recommended 80 compressions/minute and also highest number of CC is done in 2 min, While, in the other methods is less than the recommended number.