296 primary caregivers of psychiatric patients were investigated on their needs and social support, Results show that 59.8% of them think they need more money to care patients. Their psychological and physical status are not bad, but 52.4% of them think their social lives are affected. Over 50% of them encounter some difficulties in their caring, which are financial problems of caring, not understanding the prognosis of patient's disease, having fear for the recurrence of patient's disease, having trouble in communicating with patients and in helping patients be able to work. Social support systems are divided into two dimensions in this study-emotional and instrumental support. Most of emotional support networks are from caregivers' spouse, friends, children and relatives. But, instrumental support networks are mainly from psychiatric doctors and nurses. The amount of social support can not significantly influence caregivers' needfs. Sex, relationship between primary caregiver and patient, and having home care program or not can influence the amount of emotional support. But, just having home care program or not can influence the amount of instrumental support.