OBJECTIVE: To evaluate variables of tobacco health warnings associated with their emotional impact, the perception of smoking risks and the perceived effectiveness to avoid tobacco use. MATERIALS AND METHODS: Teenagers (151) and adults (168) evaluated 27 tobacco health warnings selected from the sets used on tobacco packages in Argentina and in other countries. A standardized affective rating-scale system and a structured questionnaire measured respectively the emotional impact (hedonic valence and emotional arousal), and the cognitive-behavioral attributions. The correlation between emotional and cognitive-behavioral evaluations was analyzed by age, sex, education level, smoker status,stage of quitting and susceptibility of non-smokers teenagers. RESULTS: Strong significant correlations between cognitivebehavioral and emotional assessments were observed. The warnings depicting graphic images of tobacco-related injuries and suffering were considered more valuable for tobacco. control, helping quitting and preventing initiation. CONCLUSIONS: Using graphic images with high emotional arousal is recommended for both adults and teenagers.