Previous research has documented that people with diabetes report lower psychological well-being than do people with no reported disease. In recent years, new treatment regimens for diabetes have been introduced, including improved insulin and tablet treatment, easier blood sugar tests, and transfer of responsibility from doctor to patient. Have these improved methods for controlling diabetes resulted in enhanced psychological well-being for this group of patients? In this paper, we analyze changes in psychological well-being between 1984-1986 and 1995-1997 among diabetic patients. On these two occasions, the entire adult population of one county in Norway was invited to a health screening (the Nord-Trøndelag Health Studies, HUNT 1 and HUNT 2). Participants reached 77,224 and 65,599 persons, respectively (90.7% in HUNT 1 and 71.0% in HUNT 2). The participants responded to questionnaires, including questions on several diseases and impairments, as well as self-assessed health and psychological well-being. People with diabetes reported significantly lower well-being than people with no reported diabetes in HUNT 1 as well as in HUNT 2. However, the relationship between diabetes and well-being was significantly weaker in HUNT 2 than in HUNT 1. Self-reported Subjective health, the feeling of being strong and fit, the use of Tranquilizers, and Psychological distress had improved between the two surveys, for people with diabetes compared to people with no reported diabetes. Other outcome variables - Calmness, Cheerfulness, and Life satisfaction - were only weakly related to diabetes, and the relationship did not change significantly from HUNT 1 to HUNT 2.