Purpose: The purpose of this study was to analyze the roles and tasks of dietitians working with the elderly in customized home visiting health services at public health centers. Methods: This study conducted a literature review, meetings with 3 experts, and a two-round Delphi technique with 9 experts. Results: The analysis of dietitians’ roles and tasks revealed 5 roles, 10 duties, and 30 tasks. The dietitians’ roles included registration and management of nutrition service clients, nutrition service management, internal and external linkage management within public health centers, document and supplies management, and development of job competencies. The ten duties included registration and management of nutrition service clients, nutrition assessment, nutrition service planning, implementation of nutrition and dietary education and counseling, administration of food support services, development of nutrition education and counseling programs and materials, evaluation of nutrition programs and services, internal and external linkage management within public health centers, administrative management, and professional development. Conclusions: The findings indicate that the government should ensure an adequate number of dietitians to deliver universal preventive health services for the elderly, along with a job training program to support their effective performance in these roles.