<b><i>Objective: </i></b>Parental and child co-sleeping has been suggested as a risk factor for short sleep duration and poor sleep quality that may lead to overweight. We examined if joining parent's bed during night was associated with child overweight. <b><i>Methods: </i></b>Cross-sectional data from the ‘Healthy Start' study including 635 2- to 6-year-old Danish children, who were all considered obesity prone. Of these, 496 children had complete information on BMI and whether the child joined parents' bed during night and if so, how frequently. International cut-offs for overweight according to age and gender were applied, and logistic regression was used to estimate odds ratio (OR) and 95% Confidence Intervals (CI). Analyses were adjusted for the child's age and gender, overall family stress, parental educational level, and parental BMI. <b><i>Results: </i></b>Children who did not join their parent's bed were more likely to be overweight compared to children who did (OR 1.75 (95% CI 0.99-3.10)). Children who rarely joined their parents' bed had OR 2.74 of being overweight (95% CI 1.01-7.44) compared to children who joined every night. <b><i>Conclusion:</i></b> Children who rarely joined parents' bed during night were almost three times more likely to be overweight than those who joined every night.