Early childhood caries (ECC) is influenced by microbial and host factors, including social, behavioral, and oral health. In this cross-sectional study, we analyzed interkingdom dynamics in the dental plaque microbiome and its association with host variables. The samples collected from the preschool children underwent 16S rRNA and ITS1 rRNA gene sequencing. The questionnaire data were analyzed for social determinants of oral health. The results indicated a significant enrichment of Streptococcus mutans and Candida dubliniensis in ECC samples, in contrast to Neisseria oralis in caries-free children. Our interkingdom correlation analysis revealed that Candida dubliniensis was strongly correlated with both Neisseria bacilliformis and Prevotella veroralis in ECC. Additionally, ECC showed significant associations with host variables, including oral health status, age, place of residence, and mode of childbirth. This study provides empirical evidence associating the oral microbiome with socioeconomic and behavioral factors in relation to ECC, offering insights for developing targeted prevention strategies.