<p>Although reciprocal associations between changes in parental overprotection and children’s anxiety are theoretically expected, there is a lack of empirical evidence on these linkages that tap into both between-family differences and within-family effects. This longitudinal multi-informant study examined reciprocal associations between parental overprotection and children’s anxiety at the between- and within-family level, as well as explored whether these linkages differed by informant, parental role, and children’s gender. A total of 471 children (55.2% for boys, <i>M</i>_age at T1 = 9.73, <i>SD</i> = 0.57), their fathers (<i>N</i> = 466, <i>M</i>_age at T1 = 38.92, <i>SD</i> = 4.13), and mothers (<i>N</i> = 469, <i>M</i>_age at T1 = 37.55, <i>SD</i> = 3.85) participated in a three-wave longitudinal study with one-year intervals. Results from random intercept cross-lagged panel modeling (RI-CLPM) indicated that at the between-family level, paternal overprotection, maternal overprotection, and children’s anxiety were positively correlated with each other. While at the within-family level, in the parent-reported model, children’s anxiety predicted an increase in parental overprotection after one year, with a stronger predictive effect on maternal overprotection than that on paternal overprotection, and in the child-reported model, positively reciprocal predictive effects were found between maternal overprotection and children’s anxiety over time, and in the cross-informant-reported models, maternal overprotection reported by children could positively predict the following children’s anxiety reported by parents. The above results did not differ between boys and girls. Overall, these findings highlight the importance of disentangling the between-family and within-family effects, and it is crucial to consider the perceptions of both parents and children in longitudinal research concerning the reciprocal associations between parenting behaviors and children’s psychosocial development.</p>