A group of studies revealed that family members of the seriously ill patient had some needs during the period of patient's hospitalization. Needs of the seriously-ill patient family could be classified into three aspect, i. e. needs on the prognosis of patient, needs on the well-being of family members themselves and needs on hospital enviroment. Several instrument were developed to measure the needs of the seriously ill patient, but their content tended to overemphasize the aspect of the prognosis of patient. The purpose of this study was to develop a new instrument to measure the needs in the aspect of the seriously ill patient's family themselves in details to increase the cummulative percentage of the scale. Subjects were 134 family members of the seriously-ill patients, who were being cared in ICU of seven university hospitals and data were collected from march 16, 1987 to April 11, 1987. The instrument used in this study was made by the author on the basis of results of literature review. Content valitily of the instrument was tested by a professor majoring in nursing and reliability by calculation of Cronbach's a with data of the, respondents. Data was analyzed as follows, using SAS, computer system. Factor structures of the seriously ill cpatients' family needs were elicited by factor analysis. The progromme was the Principal Component Factor Analysis Method of factoring employing Varimax Orthogonal Rotation. The influences of the demographic variables on the degree of the seriously-ill patients' family need were analyzed by t-test and F-test. Results were as follows. 1. Needs of the seriously-ill patients' family elicited and their cummulative percentage were; Needs to be supported emotionally, 29. 2% Needs to be informed on facilities available, 9.6% Needs to be informed on the patient's prognosis, 7.7%. Needs to be supported spiritually, 5.1%. Needs to be informed on hospital environment, 4.2%. Needs to be helped to spare time, 3.9%. Needs to be informed on their role, 3.5%. Needs to be present near patient, 3. 3%. 2. Educational background was found to influence on some factors. College-graduate group had higher level of needs to be informed on facilities available to be informed on the patient's prognosis, needs to be supported spiritually, needs to be helped to spare time, needs to be informed on their role than' high school graduate group. 3. Among the parents, sons and daughters and the relative groups, the parents of the seriously ill patient had highest level of needs to be present near patient. Suggestions for further studies were as follows. 1. As the instruments used in the previous studies had high cummulative percentages in the aspect of the prognosis of patient and that in this study in the aspect of the prognosis of patient and that in this study in the aspect of the seriously ill patient's family themselves, development of a new instrument which combined the items of both of them is needed.2. A study to clarify the influence of type and number of admission on need to be supported emotionally is needed.