This research aims to investigate the implementation of critical thinking (CT) in English writing as a Foreign Language (EFL) educational contexts. In this study, fifty English non-major participants attending the third Basic English at universities in Mekong Delta, Vietnam, were introduced to the concept and activities of CT. This study focused on analyzing the students’ writing attitude and performance affected by CT. The findings show that students have positive attitude on writing weekly reflection, an introduction, a survey, and the final part of a story; however telling a story is not favorite. The result also indicates that they perform well in writing advice, introduction, and their attitude to a problem. However, they are not good at giving suggestions and convincing people. The implication is for teachers to adopt and integrate CT in their practices in Asian, and the difficult tasks for the goodstudents should be applied for being optional.