ABSTRACT The purpose of this study was to examine the influence of self-care education on illness behaviors and health locus of control of Mexican American women. Participants were randomly assigned to a control (n = 60) or experimental group (n = 60). Subjects completed the Multidimensional Health Locus of Control questionnaire and an Illness Behavior Assessment at pretest and 6-months. The experimental group received a self-care manual and participated in two 2-hour seminars on how to effectively use the textbook. The experimental group demonstrated a significant increase in self-care behaviors, and significant changes in Internal Health Locus of Control and Powerful Others Health Locus of Control. Chance Health Locus of Control was found to have a low, direct correlation with age, and a low, indirect correlation with education. The conclusion of this investigation is that self-care education can positively influence illness behaviors and Health Locus of Control in Mexican American women.