PURPOSE: To measure the antimicrobial effect of Anise extract as mouth rinse in children against streptococcus mutans and lactobacilli. Material and method: A total of 60 Egyptian children from both sexes ranging from 6 to 12 years old for mixed dentition in a good physical condition. Children were randomly distributed into three groups (A, B, C) (20 children each). Group A: Patients were instructed to rinse with 40ml of anise extract (anise 1.6g/ 40ml) three times/ day, each rinse for 1 minute for 1 week. Group B: Patients were instructed to rinse with 40ml of anise extract (anise 10g/ 40ml) three times/ day, each rinse for 1 minute for 1 week. Group C (control group): Patients were instructed to rinse with 40ml of distilled water three times/ day, each rinse for 1 minute for 1 week. Results: There was statistical significant reduction in streptococcus mutans and lactobacilli count in Group B (Anise 10g/ 40ml group). Conclusion: Anise extract can be used as a preventive therapy at home to maintain oral hygiene as it is natural, safe and has no side effects.