The Internet addiction among schoolchildren has been regarded as one of the most serious social problems. Not a few researchers point out that it is important to prevent students from falling into the addiction because it is very difficult to recover from this “disease.” This paper attempts to find out risk factors for this disease on a survey we executed in primary and junior high schools in Maebashi city, Gunma prefecture, Japan. The result tells us that 8.3% of 5-6 grade primary schoolchildren and 9.1% of junior-high schoolchildren are regarded as belonging to high risk groups. LINE, online games and movie sites are remarkably popular among the risk groups. They also incline to answer to our questionnaire that they feel the learning at school as difficult, uneasy with their own family, and reluctant to attend schools.