This paper aims to examine the mediating effect of attitude toward the continued application of e-tax in the association between perceived usefulness, ease of use, compatibility, and intention to continue applying e-tax based on empirical evidence from Vietnamese tax officials. Thereby, the research model is proposed and the hypotheses are developed on the basis of the Technology Acceptance Model (TAM). This study applies a quantitative analysis with a research sample of 343 tax officials from tax authorities at all levels within Vietnam. This study applies stratified and convenient sampling techniques. Structural equation modeling with AMOS was used to test the hypothesized relationships. The results revealed that among perceived usefulness, ease of use, and compatibility only perceived usefulness has a direct impact and positive relationship to the intention to continue applying e-tax and the attitude toward the continued application of e-tax also has a direct impact and positive relationship to the intention to continue applying e-tax. Especially, the results prove the mediating effects of attitude toward the continued application of e-tax on the relationships towards the intention to continue applying e-tax. This study contributes to both the literature and practice. The limitations and future research implications are discussed.