The purpose of the study was to clarify the effects of care environment on health status of caregivers engaged in at-home medical care for their family member. Twenty-eight female caregivers were surveyed three times, i. e. one week, one month, and two months after discharge of the family member, using a questionnaire containing the Japanese version of General Health Questionnaire 12 (GHQ12) and Zarit Caregiver Burden Interview (J-ZBI). Concentrations of salivary cortisol were also measured in 28 caregivers. At one week and one month after discharge, concentrations of salivary cortisol and GHQ12 and J-ZBI scores in 28 subjects were higher as compared with previous reports in the literature. Levels of salivary cortisol significantly decreased during the period from one month to two months after discharge (p<0.05), whereas GHQ12 and J-ZBI scores did not change significantly, suggesting that their stress were physiologically decreased although psychologically they were still in high stress status. Decrease in salivary cortisol was observed greatly in the caregivers with social support and/or at lower burden of care giving. Also, scores of GHQ-12 and J-ZBI remained higher in subjects without social support or at higher burden of care giving during the study period ; GHQ-12 reflected psychological aspects of care giving stress, whereas J-ZBI were related to physical factors of care environment.