ABSTRACT We examined whether dispositional optimism and pessimism (overall LOT-R and optimism and pessimism component scores) of 694 adults aged 24 and 27 were associated with socioeconomic status (SES) measured concurrently and in childhood at ages 3 and 6. SES measures included education, occupational status and unemployment, and income. Concurrent adulthood SES was associated with the overall LOT-R and optimism and the pessimism component scores. Childhood family SES predicted overall LOT-R and pessimism component scores, even after controlling statistically for the adulthood SES. Social mobility between SES of family of origin and current SES also influenced the scores. The current findings suggest that the foundation of dispositional optimism and pessimism is related to early SES of the family.