The present study investigated self-efficacy as a predictor of adjustment to and symptomatology of sickle cell disease (SCD). Relationships between disease-specific perceptions of coping self-efficacy and indices of disease severity, health care utilization, and psychosocial adjustment were investigated at two times point (separated by 1 year) in a community based sample of African-American adults (N=147) with SCD. Perceptions of self-efficacy for coping with SCD were moderately stable across the study period (r=.42). At baseline, significant inverse relationships (p/s <.01) were noted between self efficacy and the following: physical symptoms, psychological symptoms, pain severity, and the number of physical visits over the past 12 months. Similar relations were noted at 1-year follow-up. In addition, relationship between specific efficacy beliefs and SCD adjustment were largely independent of the more global constructs of self-esteem, mastery, and internal locus of control. Finally, changes in self-efficacy from baseline to 1-year follow-up were significantly related to changes in symptomatology and health care utilization. Further analyses revealed that individuals whose self-efficacy scores declined over the 1-year study period evidenced significant increases in physical symptoms, psychological symptoms, pain severity, and number of days spent in the hospital. Collectively, the data suggest that efficacy beliefs in the SCD population are closely and uniquely related to the perceived severity and impact of the disease, and that these relationships persist cross time. Future studies need to examine the mechanisms of this relationship, and the feasability of attempting to enhance efficacy beliefs.