Objective: Family-based physical activity interventions have the potential to reduce obesity, but more information is needed regarding physical activity in the family context. This study used an actor–partner interdependence model to estimate the dyadic association between perceived weight status and barriers to physical activity in dyads of adults and their adolescent children. It was hypothesized that greater perceived weight would be associated with greater barriers perceived by both one’s self and one’s partner. Method: Data from 1,568 dyads in the Family Life, Activity, Sun, Health, and Eating study were used to examine the dyadic association between perceived weight status (i.e., greater perceived weight category) and barriers to physical activity. Models were stratified by actual weight (an overweight or obese dyad member vs. two normal weight dyad members) and adjusted for parent education, parent and adolescent age, gender, and race. Results: Among dyads with at least 1 overweight/obese member, greater perceived weight status was positively associated with one’s own perceived barriers (significant actor effects, βs = 1.17 and 1.03, ps < 0.01) and one’s partner’s perceived barriers (significant partner effects, βs = 0.38 and 0.62, ps < 0.01). No statistically significant relationships were found for dyads with only normal weight members. Conclusions: Among dyads with at least 1 overweight or obese member, significant partner effects for parents and adolescents demonstrate that the weight perception of 1 dyad member correlates with the barriers of the other member. These dyadic associations highlight the potential importance of family-based interventions for physical activity.