The aim of this study was to evaluate the concordance of parents’ assessments of their child’s dental fear. Cross-sectional secondary analysis used data from the multidisciplinary FinnBrain Birth Cohort Study. Child dental fear was assessed at age 5 with the Finnish translation of the modified Children’s Fear Survey Schedule Dental Subscale (CFSS-M) by both fathers (n = 588) and mothers (n = 1100). Reply alternatives were from 1 = not afraid to 5 = very afraid and 6 = no experience coded as missing and 1. In total, 514 mother–father pairs were eligible for the analyses. Descriptive statistics, percentage agreement and Cohen’s Kappa coefficients were used in the analyses. The concordance of parents’ assessments was poor (Kappa range 0.072–0.258). The majority of parents replied “No Experience” to items related to invasive treatment or being unable to breathe. Thus, coding of this reply alternative had a significant impact on the mean values of the child’s fear. When assessing the fear of a five-year-old child, it might not be safe to rely only on one parent’s assessment, and whether or not the child has experience with the question asked should also be considered.