The aim of present study was to evaluate the salivary sialic acid levels in Acute Lymphoblastic Leukemic (ALL) children and to correlate it with dental caries experience. Method- A total of 120 children aged 4-10yrs were divided into 4 groups of 30 each. Dental caries experience was recorded followed by un-stimulated saliva collection. Results- The mean salivary sialic acid levels of the study group were much higher when compared with the control group, which was statistically significant. A linear relationship between salivary sialic acid levels and dental caries in leukemic children was observed. Conclusion - The findings of our study conclude that salivary sialic acid levels may have a potent activity in dental caries process and can be used as a useful marker in cancer.