This study explored the effectiveness of Task-Based Instruction (TBI) in enhancing students' fluency and appropriacy for oral communication skills (OCSs) as well as students' and teacher's perception about TBI at Government Boy's Model Primary School Rahmatpur, District Khairpur Mirs, Rural Sindh. The study involved Grade five students who were exposed to Task-Based Instruction approach involving them in task activities, placing an emphasis on functional use of language. The data was gathered through classroom observations, audio recording, semi-structured interviews, field notes, reflective journal and oral pre-test and post-test. Semi-structured interviews were conducted (before and after intervention) to explore the teacher's and students' perception about enhancement of OCSs and TBI approach. Oral pre-test before intervention and post-test after intervention were also conducted to assess the improvement of the focused students in OCSs. Data was analyzed qualitatively to investigate the effectiveness of TBI approach in enhancing students' OCSs. The investigator expected that this study would demonstrate students' and English language teacher's general perceptions of Task-Based Instruction Findings of this study revealed positive impacts of TBI approach in enhancing students' fluency and appropriacy. This study also helped English language teacher in teaching OCSs. As a result, teacher took content from English text book and converted into task activities according to a task-based approach, so that students could participate in oral practice of language use actively and improve their oral communication skills.