Background and Aim: The aim of the present study was to evaluate the cephalometric changes in Class II division 1 mandibular deficient patients treated with Farmand functional appliance. 

Methods and Materials: Twenty-seven subjects (17 girls and 10 boys) with the mean age of 11.1±1.4 years were involved in the present study. All the subjects were treated with Farmand functional appliance. Paired t-test and Wilcoxon test were used to evaluate the data. The significance level was set at P<0.005.
Results: A skeletal Class I relationship and a marked reduction in the overjet were achieved with the use of Farmand appliance. ANB decreased significantly by 3.2±1.7 degrees, while SNB increased from 74.3 ±1.7 degrees to 77.6±2.3 degrees (P<0.001). 
Conclusion: The results showed that Farmand functional appliance is effective in the treatment of mandibular deficiency in patients with Class II division 1 malocclusion.