Maternal anxiety can have a significant impact on a child's behavior. This study aimed to investigate the association between maternal anxiety and externalizing and internalizing behavioral problems in their offspring. Data were utilized from 530 mothers and their 740 children participating in the 1993 Pelotas Birth Cohort and the 1993 Cohort-II study, respectively. Maternal anxiety was assessed at ages 18 and 22 using the Mini International Neuropsychiatric Interview (MINI). At age 22, mothers completed the Child Behavior Checklist (CBCL) to assess externalizing and internalizing behavior problems in their children (aged 16 months to 10 years). Two samples were analyzed: one included all children, and the other was a subsample that included only one child per mother. In one-child-per-mother sample, children of mothers with anxiety had 4.63 (95 % CI: 2.28
6.97), 3.35 (95 % CI: 0.92
5.77), and 4.97 (95 % CI: 2.51
7.43) points higher scores on internalizing, externalizing, and total problem scales, respectively, compared to children of mothers without anxiety. When including all children, the differences were 2.68 (95 % CI: 0.93
4.44), 2.63 (95 % CI: 0.73
4.52), and 2.60 (95 % CI: 0.87
4.34) points, respectively. Understanding the mechanisms underlying this association, emphasized by these findings, is crucial for promoting children's mental health and well-being, as well as developing effective interventions to support both mothers and children.