Objective To explore the influence of family factors on physical activity behavior of central obesity patient.Methods A questionnaire investigation to 182 central obesity volunteers was carried out in a residential district of shanghai on April 2007.Results The percentage of the patients taking physical activities,at least one of whose family members participate in regular exercise,was 66.7%.It was significantly higher than that (43.6%) of other patients whose family members hardly ever participated in regular exercise any more(χ2=9.260,P=0.002).The percentage of patients taking physical activities,with highly family function,was 60.2%.It was significantly higher than that of the patients in moderately dysfunctional family (49.9%) and in severely dysfunctional family(35.5%)(χ2=6.448,P=0.04).The average APGAR score,Partnership score and Growth score of the patients in taking exercise group were 7.13±2.63,1.49±0.71 and 1.35±0.73. They were significantly higher than that of the patients in taking no exercise group (6.09±3.09,1.24±0.85 and 0.90±0.86) (t=2.095～3.845,P=0.000～0.038). While family size,family economic status and marital status showed no obvious effect on physical activity behavior of central obesity patients(χ2=0.027～1.709,P＞0.05).Conclusion Highly family function and at least one of the other family members taking regular exercise can promote activity of central obesity patient in daily life.