The purpose of this article is to discuss determinants of computer self-efficacy from the perspective of participant internal learning motivations and external learning environments. The former consisted of three motivations--interest, trend, and employment--while the latter comprised two environments--home and school. Through an intermediate variable--computer use--a causal model was constructed to analyze how the determinants affected participant computer self-efficacy. To validate the model, 235 vocational and technology college and university students were surveyed. The results indicated that computer use and interest motivation had significant direct effects on participant computer self-efficacy, as did school environment and trend motivations, but the latter was negative. The home environment and employment motivations had indirect effects on computer self-efficacy through computer use, as did the interest and trend motivations. Among the correlations of determinants, the home environment was significantly correlated with all of the learning motivations, but school environment was not. Demographic analysis indicated that most of the students were not satisfied with the learning environment of schools. The results could provide useful and practical information for educational administrators, computer instructors, and students. (Contains 3 tables and 2 figures.)