Purpose: The purpose of this study was to examine the relationship of uncertainty to pain, self-care agency and health conservation and to identify factors affecting uncertainty in elderly women with osteoarthritis. Methods: Participants, 156 women aged 65 years or older, were outpatients at A orthopedic clinic in D city and were diagnosed with osteoarthritis. Data were collected using the Visual Analogue Scale (pain), Self-As-Carer Inventory (Geden & Taylor, 1988), Health Conservation Scale (Sung, 2005a) and Mishel Uncertainty in Illness Scale (Mishel, 1988) and analyzed using t-test, one-way ANOVA, Pearson's correlation, and stepwise multiple regression. Results: Uncertainty was positively correlated with the degree of pain and negatively correlated with self-care agency and health conservation in elderly women with osteoarthritis. Health conservation was the strongest predictor (β=-.28) of uncertainty in elderly women with osteoarthritis, followed by assistance from spouse (β=-.25) and monthly allowance (β=-.24). These variables accounted for 29% of the total variance in uncertainty. Conclusion: Findings from the study suggest the need to develop and utilize nursing interventions targeting improvements in health conservation to reduce uncertainty in elderly women with osteoarthritis.