This study aims to explore how Form-Focused Instruction (FFI) in a CLT context would affect Korean EFL university students’ oral communicative competence as well as their perceptions. Fifty two students participated in this study, and 26 in the FFI class were instructed to learn specific grammatical features with communication skills; whereas the rest of 26 in the non-FFI class were never given any grammar instruction or feedback. The two classes’ performance on the group oral conversation test and their responses to the survey questionnaire were, respectively, compared. The test results showed that the FFI class students outperformed those in the non-FFI class in all areas including grammar, vocabulary, content, fluency, turn-taking, and non-verbal behaviors. In addition, the survey results demonstrated that the FFI class students thought they had improved particularly grammar and fluency, and thus gained greater confidence and motivation; whereas the non-FFI class students were concerned much about their grammatical correctness which made them difficult to continue conversation. It can be thus confirmed that FFI in a CLT classroom would help students enhance their communicative competence and confidence.