This paper uses the theoretic framework of TOE(technology-organization-environment), identifies the factors promoting and hindering informatization of nursing institutions for the aged. This case study of six nursing institutions for the aged finds that different ownership institutions have some different factors promoting and hindering the process of informatization. In general, compared with public nursing institutions for the aged, private nursing institutions have more both promoting and hindering factors in technological and organizational aspect, but less hindering factors in the environmental aspect; and, risk management is an important promoting factor in the application of information systems for these institutions, it is fewer reported in other industries’ study. These findings extend the application field of the TOE theory; extend the informatization study in nursing institutions for the aged. In practical,we suggest that different ownership’s nursing institutions for the aged should take good advantage of promoting factors considering their own resources, overcome the hindering factors to ensure the successful implementation of the informatization.