This research study utilized the framework of digital inequality proposed by DiMaggio and Hargittai (2001) to examine the relationships among the subdimensions of Internet inequality and their outcomes. We firstly investigated the relationships between constructs of technical apparatus, autonomy of use, availability of social support, variation of use at different locations of Internet access (school, home, Internet cafe, and combinations of these locations) and Internet self-efficacy (ISE). Then the relationships between ISE and high school students' exploratory behavior and academic were also investigated. The survey was developed from reliable instruments used in previous research to measure the following variables: Internet Self-Efficacy, Internet accessibility at home and school, exploratory behaviors, academic performance, study use, leisure use, parents influence, superior influence, and training support. Internet access at the Internet cafe, gender, and self-reported academic achievement were added to the student survey. Bivariate correlation and regression statistical analyses were conducted to find significant relationships among these variables. ANOVA statistical analysis was used to find significant differences among groups. Significant findings indicated that digital inequality in Internet existed in school, home and Internet cafe and students with Internet access at home had the highest level of ISE. Our study also showed that different dimension of Internet inequality had different relationships with ISE. Home Internet accessibility positively related to ISE. Availability of social support from school had a greater effect than that from home as parents influence did not associate with ISE. And last, the variation of use was also related to ISE. Leisure use at Internet cafe, leisure use at home and study use at home positively associated with ISE. In addition, at home and Internet cafe, the relationship between leisure use and ISE was stronger than that between study use and ISE. As to the outcome of ISE, high levels of ISE were positively related to exploratory behaviors, and for those students who used the Internet at school and home, higher ISE related to better academic performance.