At present head louse infestation or pediculosis is a common problem worldwide, especially among school children. A preventive approach to the maintenance of good health with specific education can be of greater benefit to a person than a delayed reactive one. The aim of the study was to find out whether the Neem leaves powder is effective in prevention and control of pediculosis among school children. The conceptual frame work was developed based on VonLudwig Bertalanffy (1968) system theory. The quasi experimental one group time series with multiple application was adopted for this study. The study was conducted in paraniputhur village at Thiruvallur District. By using purposive sampling technique, 30 samples were selected. The duration of the study was three weeks. Pretreatment assessment was done by using observational check list based on signs and symptoms of pediculosis infestation. On the same day neem leaves powder paste was applied, on the third day post treatment assessment was done. The treatment was continued for 6 times in the same manner. The same tool was used to assess the degree of pediculosis infestation throughout the study. Data collected was analyzed by using descriptive and inferential statistical methods. The study finding showed that 15(50%) had mild degree of pediculosis infestation and 15(50%) severe degree of pediculosis infestation before application of neem leaves powder. During 1st and 2nd application it remain the same but after 3rd, 4th, 5th and 6th application there was a gradual decrease in pediculosis infestation and 30 (100%) had mild degree of pediculosis infestation. Hence there was a significance difference between pretreatment and post treatment there was no significant association found between the degree of pediculosis infestation prior treatment with the demographic variables. The study concluded that neem leaves powder is very effective, cheap and non irritant and helps in control and prevention of pediculosis infestation.