There are many determinants of children’s dental caries. We hypothesized that a mother’s untreated caries was associated with increased likelihood of her children’s untreated caries, after controlling for other factors. This population-based study was conducted in a rural, primarily Hispanic, California community. Interview and dental examination data for mother-child (children < 18 yrs old) dyads were analyzed. In a Generalized Estimation Equation (GEE) logit model for mothers (n = 179) and children (n = 387), maternal untreated caries was a statistically significant correlate of child’s untreated caries, odds ratio (OR) = 1.76 (95%CI: 1.10, 2.70), adjusted for demographic factors. This relationship did not change when behavioral and dental utilization factors were added to the model, OR = 1.85 (95% CI: 1.12, 3.07). Maternal untreated caries almost doubled the odds of children’s untreated caries and significantly increased child’s caries severity by about 3 surfaces. Caries prevention and dental utilization programs for mothers and their children should be increased.