This cross-sectional study aimed to investigate the psychological factors that might predict the sedentary behavior of 654 older adults from the South Region of Brazil. The participants were evaluated by the International Physical Activity Questionnaire; Mini-Mental State Exam; Geriatric Anxiety Scale; and the scales Geriatric Depression, Purpose in Life, Perceived Stress, Rosenberg Self-Esteem, and Satisfaction with Life. Data analysis was conducted through Pearson correlation and multiple regression analysis (p < .05). No significant (p > .05) correlation was found between the sedentary behavior variables with self-esteem. Multiple regression analysis revealed that psychological variables explained 6% of the variance of sitting time during the week (R2 = .06; F = 11.546; p < .01). Depression showed a positive prediction (β = −0.10; p = .040), while life satisfaction (β = −0.16; p = .001) and purpose in life (β = −0.10; p = .026) showed negative prediction. Psychological variables predicted only 3% of the variance of sitting time during the weekend (R2 = .03; F = 5.629; p < .01), showing that life satisfaction had significant (p = .007) and negative (β = −0.13) association. Life satisfaction and purpose in life can be considered protector factors to sedentary behavior, while depression is a potentiating factor.