BACKGROUND: At present, China has become the country with the largest number of individuals with diabetes mellitus (DM) in the world, with a total of approximately 140 million patients, the majority of whom have type 2 DM (T2DM). Based on conventional nursing methods, community home care has important clinical significance in controlling blood sugar and disease progression. AIM: To explore the impact of community public health nursing on treatment effect, health cognition, and self-management in patients with T2DM. METHODS: One hundred patients with T2DM were selected as the research subjects. The patients were divided into either a conventional nursing group or community nursing (CN) group using the random number table method. The conventional nursing group (50 cases) received routine care, while the CN group (50 cases) received community public health care in addition to routine care as that for the conventional nursing group. The rate of excellent and good blood glucose control, fasting blood glucose before and after care, 2-h postprandial blood glucose, health cognition, and self-management ability, and patient satisfaction were compared between the two groups. RESULTS: The CN group had a higher rate of excellent blood sugar control than the conventional nursing group (88% CONCLUSION: Community public health care based on conventional care of T2DM can achieve better blood sugar control, and improve patients' health cognitive level and self-management ability.