BACKGROUND: Relatively little research has examined cognitive processes that may impact psychological adaptation in older long-term breast cancer survivors (BCS). PURPOSE: This study investigated the strength of a conceptual model based on the literature and Uncertainty in Illness Theories which proposes that negative mood state and personal growth in older long-term White and African American BCS would be predicted by the combined influences of demographic and disease variables, social support, religious participation, and cognitive processes (uncertainty, catastrophizing, troublesome thoughts, and cognitive reframing). METHODS: Baseline data were gathered from 524 BCS (369 Whites and 155 African Americans, 5-9 years postdiagnosis) prior to their participating in an uncertainty management intervention program. The conceptual model was tested using structural equation modeling. RESULTS: The multigroup model showed good fit to the data and explained substantial variance in negative mood state and personal growth. Cognitive processes showed both direct and indirect effects on outcomes in the expected directions. Several ethnic differences were found: African Americans were more negatively affected by comorbidities and Whites by symptom distress, whereas cognitive reframing was a stronger predictor of personal growth for African Americans than Whites. CONCLUSIONS: This is one of the first studies to explore predictors of both negative mood and personal growth in a multiethnic sample of BCS. These findings suggest that cognitive processes play an important role in psychological adaptation to breast cancer survivorship. These processes are amenable to change, suggesting a logical target for intervention with this population.