To determine whether psychosocial variables are related to long-term glycemic control; trait anxiety, depression, loneliness and life stress were assessed in 48 Type I diabetic patients. Hemoglobin A1c (HbA1c), an indicator of long-term glycemic utilization, was assayed from blood samples drawn shortly before the self-report instruments were administered. Of the psychosocial variables, anxiety was significantly related to current values of HbA1c. The association between anxiety and current HbA1c remained after statistically controlling for potentially confounding variables, including the previous value of HbA1c. Despite the stability of HbA1c values over time, anxiety scores were not significantly correlated with follow-up HbA1c. The implications of the significant relationships between psychological constructs and glycemic control are discussed.