The purpose of this research was to examine the relationships among health locus of control, basic conditioning factors of age, duration of education and self-care agency in prostitute women. The purposive sample consisted of 200 prostitute women under the care of Women Health Clinic, Bangrul Hospital. Self-care agency was measured by the Appraisal of Self-Care Agency Scale developed by Ever, et al. (1985). The health locus of control was measured by Multidimensional Health Locus of Control Scale developed by Wallston, et al. (1978). The results of the study indicated that there were no significant relationships between internal health locus of control, powerful other health locus of control and self-care agency. However, chance health locus of control was negatively correlated with self-care agency. As to the relationships between basic conditionign factors and self-care agency, it was found that self-care agency was not correlated with age but was positively correlated with durationof education. When all dimension of locus of control and basic conditioning factors were entered into the regression model to predict self-care agency, only duration of educatio was a significant perdictor, and accounted for 14.8% of variance in self-care agency which was statistical significant. The findings give little support of Orems proposition in that self-care agency is conditioned only by duration of education. The limitations of this study and suggestions for further study were recommended.