The current study examined associations between maternal negative affectivity (NA) and child disruptive behavior problems. The mediating role of child callous-unemotional (CU) traits in these relationships was also investigated. A multilevel mediation modeling approach was adopted using a sample of 100 families with children between 2.5 and 5.5 years of age ( N = 201; mean age = 3.8, standard deviation = 1.0). The mediation models showed significant mediating effects of maternal NA through CU traits for ADHD ( β = 0.12, p <.01), ODD ( β =0.13, p <.01), and aggression ( β =0.16, p <.001), and a significant direct effect for aggression ( β = 0.12, p <.05). A structural equation modeling analysis was also performed, and overall, the results were consistent with that from mediation models, which suggested that child CU traits were significantly correlated with maternal NA ( β = 0.252, p <.001), ADHD ( β = 0.504, p <.001), ODD ( β = 0.545, p <.001), and aggression ( β = 0.686, p <.001). Our results indicated that maternal NA could serve as a potential risk factor for child CU, which, in turn, may contribute to disruptive behavior during early childhood.