The purpose of the study was to investigate dispositional optimism, self-efficacy, and explanatory style among gifted and non-gifted secondary school students in terms of gender and developmental stages. Questionnaire data were collected from 295 gifted and 437 non-gifted students. The results of the study were as follows: (1) There was no significant difference in optimism and pessimism scores between the gifted and the non-gifted secondary high school students, but the female students rated higher on optimism than the male students. (2) The gifted students had higher self-efficacy than the non-gifted students. (3) The gifted junior higher school students had a more optimistic explanatory style compared to their non-gifted junior high school peers. On the other hand, the non-gifted junior high school students had a more pessimistic explanatory style than the gifted junior high school peers. (4) The gifted senior high school students had a more pessimistic explanatory style compared to the gifted junior high school students. Based on the findings, the authors proposed suggestion for future studies and future counseling services provided to gifted students.