An innovative teaching approach of Teaching English to Speakers of Other Languages (TESOL) such as Task-based Language Teaching (TBLT) plays a vital role in the effective teaching and learning of second language skills, specifically the oral communicative skills. Thus, the teachers’ professional development according to the need of time is very important, because learners’ learning of second skills depend on the content and pedagogical content knowledge of teachers. In Pakistan most of the student at public and private schools are observed by performing poorly in their oral communicative skill of English language during the process and after completing their graduations due to several factors highlighted by different studies (Ahmed, 2017; Bano, 2016). Hence, the purpose of this research was to explore the perceptions of TESOL teachers regarding TBLT as an innovative approach and its role in the improvement of the oral communicative skill of English language in grade five. The study was conducted through an exploratory case study and interviews, document analysis and observations were used as data collections tools. Data were collected from two primary TESOL teachers of urban private ABC primary school in Karachi, Pakistan. Major findings of the study were: the poor conception of by TESOL primary teachers about TBT, communicative skills, teaching of oral communicative skill, the role of teachers, leaners and teaching resources, use of local languages and the hindering factors such as the standardized exams system; the non-alignment of textbooks, exam system and curriculum development, teaching resources, teacher, student and classroom related factors. Thus, the findings of the study suggest that curriculum developers, policy makers and teacher educators must sit together for bringing about an alignment in the curriculum, textbooks and the examination system in the context of school. Furthermore, the finding of the study suggests that, the teachers by developing their professional knowledge and skill and by using the TBLT approach could improve the oral communicative skills of grade five learners. In this way the early age fluency gradually help the learners in improving of their accuracy and competency in English oral communicative skills.