The Computerized Enhanced ESL Placement Test (CEEPT) at a public university in the US reflects a new academic writing assessment as test-takers are given sufficient time to plan, produce, and revise a short, academic essay. This study examines the authenticity of the CEEPT, will illuminate the potential of the computerized process-oriented writing assessment. The authenticity was examined based on both logical and empirical analyses. A close examination of a checklist with test and Target Language Use (TLU) tasks reveals relatively good correspondence between the characteristics of CEEPT tasks and of TLU tasks, which indicates high authenticity of the CEEPT. Test takers’ responses to the open- and closed-items on the CEEPT survey also show positive evidence in support of the authenticity of the CEEPT. Students perceived a close match between the academic tasks and the CEEPT tasks, and this high authenticity contributed to eliciting their true writing abilities. The CEEPT as one possible model for process-oriented writing assessment can provide alternatives to timed-single draft essay tests. The findings in this study can advance our understanding of writing assessments and may be applicable to the Korean context.