T he study investigated the impact of corpus-based activities on enhancing EFL students' grammar and vocabulary and explored their attitudes toward using corpus. Two classes of 104 freshmen taking business English course at Sadat Academy for Management Sciences in Egypt participated in the study; with 54 in the experimental group and 50 in the control group. The mixed-methods design was used to gather data from a grammar test, a vocabulary test, a questionnaire, and semi-structure interviews. Students in the experimental group were trained to use corpus and were taught through corpus-based activities for 11 weeks; whereas control group students were instructed using the course book only. The differences in students' performance in grammar and vocabulary were examined between their pre- and post- tests. The results of the t-test indicated that there was a significant difference between the mean scores of the pre- and post-tests of grammar and vocabulary of the experimental group in favor of the posttests. Also, experimental groupstudents outperformed their counterparts in the control group in the mean scores of the grammar and vocabulary posttests. After the treatment, the attitudes of experimental group students toward corpus were explored through administering the questionnaire and interviews.  Data analysis of the questionnaire revealed that respondents were generally positive toward using corpus-based activities in learning both grammar and vocabulary. Analysis of the interviewees' responses supported the findings of the questionnaire and offeredsome insights into using the corpus. Suggestions for pedagogical implications and recommendations for further research were provided in this study