【Objective】To explore the effects of family cohesion and child-teacher dependency on children??s attention-deficit/hy? peractivity behaviors at one year after their kindergarten entry.【Methods】Based on a cohort of 7 465 first-year preschoolers in Long? hua district of Shenzhen in 2014，the information about social-demographic characteristics，family cohesion（assessed with Family Environment Scale-Chinese Version）were collected from their primary-caregivers at kindergarten entry. The teacher rating scores of child-teacher dependency（assessed with Student-Teacher Relationship Scale）and parental rating scores of attention-deficit/hyperac? tivity behaviors（assessed with Conners’Parent Symptom Questionnaire）were examined at one year after their kindergarten entry. Lo? gistic regression were performed to analyze the relationship and interaction between family cohesion and child-teacher dependency in attention-deficit/hyperactivity behaviors，after adjusting for potential confounders.【Results】Children??s attention-deficit/hyperactivity behaviors at one year after kindergarten entry were negatively associated with family cohesion（OR=0.85，95% CI=0.75~0.97，P= 0.01），but were not significantly associated with child-teacher dependency（OR=1.00，95% CI=0.93~1.08，P=0.98）. Furthermore， family cohesion moderated the impact of child-teacher dependency on children??s attention-deficit/hyperactivity behaviors at one year after kindergarten entry（OR=0.96，95% CI=0.92~0.99，P=0.03）. In addition，neither family cohesion（OR=1.08，95%CI=0.88~ 1.34，P=0.47）nor child-teacher dependency（OR=1.03，95%CI=0.93~1.15，P=0.53）could protect preschoolers from persistence of attention-deficit/hyperactivity behaviors in the first year of kindergarten.【Conclusion】The association of child-teacher dependencyand onset of attention-deficit/hyperactivity behaviors is modified by the level of family cohesion in preschool children.