Objectives: The management of type 2 diabetes mellitus can be improved for individuals by developing relationships with other patients with diabetes.We created the Relationship Consciousness of Japanese Patients with Type 2 Diabetes Mellitus scale to measure the relationship consciousness of type 2 diabetes mellitus patients for other patients based on the Health Belief Model.Methods: This was a cross-sectional study of Japanese patients with type 2 diabetes mellitus (n-289).Data were analyzed via exploratory factor analyses,reliability tests,concurrent validity.Results: The final scale obtained for the Relationship Consciousness of Japanese Patients with Type 2 Diabetes Mellitus scale comprised a six-factor structure with 36 items.All 36 items had a Cronbach’s α coefficient of 0.893 and explained 59.38％ of the total variance.The scale was significantly correlated with a related reciprocity consciousness scale.Conclusions: The Relationship Consciousness of Japanese Patients with Type 2 Diabetes Mellitus scale may be an important tool for nurses to assess the relationship consciousness of patients with type 2 diabetes mellitus.In addition,by understanding patients’ relationship consciousness for others who share their disease,nurses can begin to recommend ways to establish relationships between patients that suit patients’ particular relationship.consciousness levels and to provide better care in their clinical practice.