The present study examined the effectiveness of a shared storybook reading intervention in increasing children’s early numeracy and early literacy skills through a multiple baseline single case design. Four parent-child dyads were included in the study, and children’s early numeracy and early literacy skills were measured using the eNumeracy Early Math Assessments and the Preschool Early Literacy Indicators, respectively. The study also measured mathematical dialogue to determine if an increase in children’s early numeracy skills is due to the intervention and not other confounding variables. Finally, the study measured intervention integrity, and parent ratings of social validity. Results of the study indicated that parent-child mathematical dialogue increased for three participants and could not be calculated for the fourth participant due to attrition. Visual analysis and hierarchical linear modeling results indicated no statistically significant early numeracy or literacy outcomes across participants. A masked visual analysis indicated that there was an observable difference in children’s scores on the eNumeracy Ordinal Position measures, but none of the other outcome measures. Additionally, the majority of parents were able to implement the intervention with integrity and all parents reported high levels of social validity. The findings of this study show that the parent directed shared mathematical storybook reading intervention was effective in increasing mathematical dialogue between parents and children. Future studies should examine the impact of shared mathematical storybook reading interventions on discrete early numeracy and literacy skills specifically targeted during the book reading interventions.