According to the 2003 Youth Risk Behavior Surveillance Survey, 33% of youth in grades 9-12 participated in an insufficient amount of vigorous and moderate physical activity (PA), and 11% reported no vigorous and moderate PA. Although researchers have examined the psychological correlates of exercise behavior among youth, limited research investigating moderators of the theories of reasoned action (TRA; Ajzen & Fishbein, 1980) and planned behavior (TPB; Ajzen, 1985) in this population exists. Therefore, the main purpose of this study was to examine socioeconomic status (SES) as a moderator of the psychological correlates of exercise intention and behavior using the TRA/TPB in a youth population. The primary objectives of this study were to: (a) determine the psychological correlates of exercise intention, (b) determine the psychological correlates of exercise behavior, and (c) determine if SES moderates the relationships of the TRA/TPB constructs. It was hypothesized that attitude, subjective norm, and PBC would be significant correlates of exercise intention, and that attitude and PBC would be the strongest predictors. It was also hypothesized that intention and PBC would be significant correlates of exercise behavior, and that intention would be the strongest predictor of behavior followed by PBC. Finally, it was hypothesized that no significant differences would be observed on the TRA/TPB constructs based on SES. The final sample included 309 8th and 9th grade male and female students (M age = 14.36 years, M BMI = 22.46). Most of the participants were 9th grade students (54.0%), female (63.4%), Caucasian (72.2%), and part of families living above the median income level in Louisiana (49.8%). Participants completed measures of past exercise behavior, attitude, subjective norm, intention, and perceived behavioral control (PBC) for exercise behavior during their physical education or health classes. Consistent with previous TPB research, hierarchical regression analyses showed that attitude, subjective norm, and PBC explained 49.2% of the observed variation in exercise intention, and that PBC was the strongest predictor; however, subjective norm was a more important predictor of exercise intention than attitude. In addition, intention and PBC explained 32.7% of the variance in exercise behavior and intention was the strongest determinant followed by PBC. Finally, there was no evidence of SES moderation of the TRA/TPB constructs. More specifically, no group differences were identified for those students above the median income compared to those at or below the median income on the TRA/TPB constructs and exercise behavior. Furthermore, when the interaction terms were added to the regression models they did not add a significant amount of explained variance and none of the interaction terms were significant predictors of exercise intention and behavior. These findings support the hypotheses of the TRA/TPB in that exercise behavior is largely influenced by intention and PBC, and the findings indicate that SES is not a moderating factor of the TRA/TPB. Therefore, health care professionals, researchers, and practitioners may use this information to develop and test behavior change strategies that target intention and PBC for exercise among adolescents from varied SES backgrounds to determine if exercise behavior can be changed.