The aim of this study was to identify the reasons for the provision of informal rehabilitation services at home to stroke relatives by Thai caregivers. Twenty primary informal caregivers were individually interviewed at their homes by using semistructured questions elaborated by the researchers. All interviews were recorded on audiotape. Content analysis was used to determine the reasons for performing informal rehabilitation. Four major reasons, (i) biological, (ii) psychological, (iii) social, and (iv) spiritual, emerged from our content analysis to maintain for the stroke victims the highest possible quality of life. Improvement and prevention of further deterioration were the two main concepts in the biological and psychological reasons expressed by these Thai caregivers, whereas maintaining human relations and usual social activities were the two main considerations in the social reason. The main concepts in the spiritual reason were respecting the religious beliefs, superstitions, and culture of the caregivers or patients, improving patients' empowerment, and improving caregivers' satisfaction. These four reasons encompassed the biological, psychological, social, and spiritual aspects of a holistic approach to the definition of health. The health professional in Thailand should encourage stroke caregivers to continue providing informal rehabilitation services for their stroke relatives, as it might sustain the well being of stroke survivors during their stay at home.