This study investigates the differences in cognitive effort, revision interventions typology and revision quality of translators between translation revision (revising a human-translated text)and post-editing (revising a machine-translated text ) based on E-C translation by triangulating key-logging, retrospective protocols and questionnaires. The results show that compared with translation revision, translators spend significantly more cognitive effort measured by pause duration and number of pauses, make more necessary changes and obtain a higher revision quality in post-editing. This study demonstrates that translators have a significantly different performance in translation revision and post-editing and that factors including translators’ trust towards translation origins, types of translation errors and translators’ adherence to task instructions might exert an influence on their performance in those two tasks. The findings of this study may provide useful insights for related research including empirical research on translation revision and post-editing, the development of machine translation post-editing competence models, and the advancement of computer-assisted translation competence.