Objective: The objective of this study was to evaluate the effects of functional treatment on positional changes in tongue and to determine if any relationship exists between the functional appliance therapy in Class II division 1 and position of tongue. Material and Method: Pre-treatment and post-treatment lateral cephalographs of 30 Class II division 1 patients within the age group of 8-12 years were taken and traced. After identification of determining landmarks, reference lines were marked and 4 linear measurements were evaluated __ampersandsignndash; 2 each in horizontal and vertical plane. These linear measurements were compared for reliability using statistical analysis. Results: Statistically significant (p __ampersandsignlt; 0.05) differences were found in linear measurements indicative of alteration in tongue position in horizontal and vertical direction. There was a significant interrelationship between reduction of ANB angle and movement of tongue in forward direction. Conclusion: The results suggest that Functional appliances are very effective in altering the position of tongue during treatment of Class II division 1 malocclusion.