This study was conducted. to test the adequacy of fit of the one-factor and two-factor models of optimism and pessimism, defined as positive and negative outcome expectancies. We also examined the differential patterns of correlations between separate optimism and pessimism measures and several criterion variables such as psychological well-being(i.e., self-esteem, depression, anxiety, positive affect, negative affect), career attitude maturity, and coping(i.e., positive reframing, seeking social support, focusing on problem-solving, tension reduction, wishful thinking, denial). Exploratory factor analysis supported the existence of two factors, optimism and pessimism. Confirmatory factor analysis yielded the results that the two-factor model of optimism and pessimism as related constructs fits the data best. There was a moderate degree of negative correlation between optimism and pessimism. Zero-order correlations showed that those with higher optimism reported the higher levels of wishful thinking and independence in career decision, which were not significantly correlated with the level of pessimism. Those with higher pessimism reported the higher levels of tension reduction and denial and the lower levels of career goal-directedness, which were not significantly correlated with the level of optimism. However, those with higher optimism reported the higher levels of self-esteem, positive affect, career decisiveness, career preparedness, career confidence, positive reframing, social support, and problem-solving focused coping, which were negatively correlated with pessimism. Those with higher pessimism demonstrated the higher levels of depression, anxiety, and negative affect, which were negatively correlated with optimism. Further, partial correlations between optimism and criterion variables after controlling for pessimism, and partial correlations between pessimism and criterion variables after controlling for optimism remained significant. The results of this study provide support for the idea that optimism and pessimism are differentiable, bur somehow related, constructs. Implications of the present findings for future research on optimism and interventions for adolescents experiencing psychological distress and career-related problems were discussed.