This paper investigated the gender differences in junior high school students' Internet self-efficacy and their use of the Internet. A total of 1080 eighth graders were randomly selected from all junior high school students in Taiwan. The Internet Self-Efficacy Scale (ISES) was developed and used to examine students' Internet self-efficacy in two dimensions: "online exploration" ("explorative ISE") and "online communication" ("communicative ISE"). A survey including the ISES instrument was administered to all the subjects and finally 936 valid questionnaires (from 466 males and 470 females) were returned for data analyses. No significant gender difference was found in students' total ISE and explorative ISE; however, a significant gender difference was found in students' "communicative" ISE. Surprisingly, the girls had significant higher communicative ISE than had the boys. In addition, there was no significant gender difference in students' Internet using experience and computer ownerships; however, there were significant gender differences in their Internet using purpose and intensity. In spite of the boys showed a significantly higher Internet use intensity than did the girls, the boys were more exploration-oriented Internet users and the girls were more communication-oriented Internet users. And this orientation played a significant role in their Internet self-efficacy. These results suggested that the gender gap may no longer exist in young students' confidence in using the Internet. However, boys and girls used the Internet for significantly different purposes suggesting that the Internet played different roles for boys and girls in Taiwan. With a large scale examination by using a valid and reliable instrument, this study provided representative results for further related studies. (Contains 12 tables and 3 figures.)