Background: Heavy internet use effect the academic achievement of adolescent and negative effects. When compare about Facebook users and Non Facebook users found that Facebook users CGPA is lower than Non Face book users. Because Facebook users spend lots of time in Facebook and every day they used Facebook. Heavy use of internet is a part of daily life.as.

Methodology: A quantitative approach with cross sectional descriptive survey design was adopted for the study. The samples from the selected high schools of Belagavi district were selected using convenient sampling technique. The sample consisted of 60 high school students. The tools used for data collection was structured internet addiction scale and structured knowledge questionnaire.

Results: The internet addiction test scores of respondents mean was 39.68, median was 39, mode was 43 with standard deviation 13.30 and score range was 16-71 the knowledge scores of respondents mean was 12.65, median was 13, mode was 13 with standard deviation 4.06 and score range was 5-20. Majority 39(65%) respondents were moderately addicted, 17 (28.3%) respondents were affected mildly and remaining 4(6.7%) of respondents were severely affected with internet addiction. majority 37(61.7%) of respondents were had moderate knowledge, 13(21.7%) of respondents were had poor knowledge and remaining 10(16.7%) of respondents were had good knowledge regarding impact of internet addiction on health.

Conclusion: There is a need for the awareness program on effects of excessive use of internet among student groups to minimise its physiological, psychological and social effect among the adolescent age group.