Child hunger was prevalent during the COVID-19 pandemic, but the extent, determinants, and impact on pre-school children aged 6 months to 7 years old from Malaysian urban poor households are still unknown. This exploratory cross-sectional study was performed between July 2020 and January 2021 at the Lembah Subang People Housing Project, Petaling. The households’ food security status was assessed using the previously validated Radimer/Cornell questionnaire, and the children’s anthropometric measurements were taken. Food diversity score was assessed using the World Health Organization Infant and Young Children Feeding (under-2 children) or Food and Agriculture Organization Women’s Dietary Diversity (2-year-old-and-above children) systems. Overall, 106 households were recruited. The prevalence of child hunger is 58.4% (95% CI: 50.0, 67.4). Significant differences were found in breastfeeding and sugar-sweetened beverage consumption between under-2 and ≥2-year-old children. There were no significant differences between child hunger and other food-insecure groups in weight-for-age, height-for-age, and weight-for-height z-scores. Only a higher dietary diversity score was significantly protective against child hunger after adjusting for maternal age, paternal employment status, and the number of household children (ORadjusted: 0.637 (95% CI: 0.443, 0.916),p= 0.015)). Proactive strategies are warranted to reduce child hunger during the COVID-19 pandemic by improving childhood dietary diversity.