Objective To develop a questionnaire to assess family support needs of institutionalized elderly persons, and to test the reliability and validity. Methods Based on the social support theory and nurse-patient communication model, a 45-item initial questionnaire assessing family support needs of institutionalized elderly persons was formulated after literature review, semi-structured interview, group discussion, and expert consultation. Then 334 institutionalized elderly persons were invited to complete the questionnaire and 6 experts were consulted to test the reliability and validity. Results Four factors of 38 items were identified through exploratory factor analysis, which could explain 64.268% of the total variance. The content validity index was 0.927, the Cronbach′s α coefficient was 0.962, the test-retest reliability was 0.952, and the split-halfreli ability was 0.836. Conclusion The questionnaire is reliable and valid for assessing family support needs of institutionalized elderly people.