For Nigeria to attain her Vision 20: 2020, the school curricula must change in line with the development in technology. Teachers should be able to adapt technology into the teaching and learning process. Three non-intellectual elements that affect the degree of integration of technology into teaching and learning are attitude toward computer, computer anxiety and computer self-efficacy. The study investigated attitudes towards computer, computer anxiety and gender as determinants of computer self-efficacy among 2100 pre-service science, technology and mathematics (STM) teachers from the University of Lagos of Nigeria using the quantitative research method within the blueprint of the descriptive survey design. Data collected were analysed using the descriptive statistics of percentages, mean, and standard deviation and inferential statistics of independent samples t-test, Pearson product-moment correlation coefficient and multiple regression analysis. Finding revealed significant correlations between computer attitudes, computer anxiety and computer self-efficacy. Gender differences in attitude toward computer, computer self-efficacy and computer anxiety among pre-service STM teachers were significant. Affective component; perceived control component; perceived usefulness component; behavioural intention component; gender; and computer anxiety made statistically significant contributions to the variance in pre-service STM teachers' computer self-efficacy. The study recommended among others that academic institutions should pay more attention to this computer anxiety and adopt proper ways of reducing the computer anxiety. This will enable positive e-learning experiences to be created for pre-service STM teachers.