Objective: ECC is a big problem facing our children in Mansoura city so this study was done to evaluate the knowledge and attitude of mothers toward ECC, determine the possible risk factors of ECC and determine the relationship between the caries experience of the mothers and the ECC experience of their children. Materials and Methods: A cross sectional study was done among 1500 mother and their children aged 1-4 years old. This study was based on close ended qestionnaires interview, in addition to salivary samples collection from 150 mothers and their children to detect the Streptococcus mutans counts in saliva. Results: About half of mothers or sometimes more significantly reported correct knowledge regarding most of the questions (p=0.001). Significant percentage of mothers had positive attitudes regarding all questions except for visiting the dentist for pain only and the main reason for visiting the dentist. Regarding the bacterial count, only 21.3% of the mothers had high bacterial counts with no statistical difference. As for children, 34% of them had high count with no statistical difference. Conclusion: Correct knowledge of the mothers is considered relatively low, while the positive attitude is considerably fair.