Man’s deep-rooted tendency to maintain and reinforce a positive self-image makes man inclined to uncritically accept desirable information (the confirmation bias) as well as to criticize and reject undesirable information (the disconfirmation bias). Since disconfirmation strategy leads to a logically correct solution to the four-card Wason selection task, we predicted that ego-involvement manipulation would have a significant effect on the success rate of the task. Specifically, we hypothesized that subjects who were exposed to personally threatening information would try to reject it and thus be more successful on Wason task than those who were exposed to non-threatening information, as established in previously published study by Dawson et al. (2002a). Furthermore, we wanted to examine if manipulating valence framing of the Wason task rule would result in a higher success rate for the group exposed to the threatening and negatively framed rule (that implied their own early death) than the group exposed to the threatening but positively framed rule (that category of people other than the one they belong to live longer). One hundred ninety five high school students from Kragujevac, Serbia participated in the experiment. The results confirmed the expected effect of involvement, while the main effect of framing did not occur. However, there was a marginally significant involvement by framing interaction: unexpectedly, non involved participants were more likely to solve the task correctly when it was positively framed than when in was negatively framed, whilst in the involved group there was no difference in correct responding depending on framing. The findings suggest that the success rate in Wason task can be sensitive to the valence framing of the rule, but only when respondents are not highly personally threatened. Potential methodological interventions in ego-involvement manipulation and content of the rules are discussed.