Introduction: The purpose of this study was to compare the structure of families with AIDS patients and that of the healthy families. The two main hypotheses were to examine the significant difference between cohesion and flexibility of these families, and between reported cohesion and flexibility in males and females. Method: The sample included 200 healthy families and 200 of HIV/AIDS patient’s families that were selected using cluster and available sampling procedures respectively. Participants completed FACES-IV questionnaire. Inclusion criteria were participation of at least 3 members of family. Results: MANOVA revealed that there was significant difference between the structure of healthy families and those who have patients with HIV/AIDS. Also there was significant difference between reported cohesion and flexibility of male and female participants. Conclusion: there were both individual and familial factors that affect the structure of these two types of families, including the patient’s personal attitude towards the disease, the patient’s schematic concerning the disease, as well as the behavioral factors of the patient. The familial factors include the stigma concerning HIV/AIDS, the care and treatment by the family for the patient, and other reactions by the family towards factors such as stigma