Children obesity is a serious public health issue . This study aimed to investigate physical/sedentary activities of first-year primary schools children in Modena, and their association with overweight/obesity and dietary habits of children and family characteristics to identify the risk factors for unhealthy lifestyles . Child physical/sedentary activities were gathered through an anonymous questionnaire administered to parents, as well as family characteristics and weight/height of child and parents . Logistic regression models, eventually adjusted for parents ’ sociodemographic characteristics, were used to analyze data . Questionnaires were delivered by 660 families (74.2 %), of which 72 without anthropometric data were excluded . Three out of four children spent in physical activities less than 7 h/week, while 63.9% dedicated to sedentary activities two or more hours/day . From multivariate analysis, the habit significantly affecting children ’ s overweight/obesity was spending time on tablets/Personal Computers/mobile phones/videogames . Higher parental education level resulted in a protective factor for implementing unhealthy lifestyles in terms of time dedicated to physical/sedentary activities . Our results suggest the need of interventions to increase time for physical activity and to promote a responsible use of digital media involving the entire families to reach all parents regardless of their education and nationality with a possible relapse on other family members.