The rapid growth of higher education institutes (HEIs) at public and private sectors has raised a key concern for quality among all stakeholders of higher education both nationally and internationally. To tackle this expansion, the Government of Pakistan established the Higher Education Commission (HEC) in 2002. A national Quality Assurance Agency (QAA) was established in 2005, under the jurisdiction of HEC, for the purpose to specifically look after quality issues in Pakistan. The QAA is actively engaged to assure the quality of education for more than one decade, but there are still issues related to quality in higher education. Therefore, this qualitative study was conducted to explore HEC's guided QA mechanisms for assuring the quality of teaching, learning and research at the graduate level, its effectiveness and influencing factors in the context of Khyber Pakhtunkhwa. A qualitative multiple case study approach was employed to achieve the aim of this study. The data were collected from two selected universities in the context of Khyber Pakhtunkhwa with the help of face to face interviews and relevant documents analysis. Through purposive sampling technique, the participants for the study were selected from quality enhancement cell and education department, which included, deputy and assistant director of QEC, Head and focal person of the education department, MPhil and PhD students from the selected universities. Whereas, at HEC, two deputy directors from QAA were also interviewed. The data were analysed using within and cross-case analysis technique with the thematic approach. The study found that various HEC's guided mechanisms are used in the selected public and private-sector University respectively. The purpose of these mechanisms is to assure the quality of teaching, learning and research at the graduate level. Cross-case analysis demonstrated five mechanisms, which were common in both universities. These are: 'establishment of quality enhancement cell' (QEC), 'Self-assessment report' (SAR), 'collection of feedback from stakeholders', 'discouragement of plagiarism in research', 'evaluation of dissertation and publication of paper in PhD'. The findings revealed some of the effectiveness of these mechanisms such as, developing a sense of responsibility and motivation among stakeholders, improving quality of teaching, learning and research by developing quality culture, strengthening the internal quality assurance system, and promoting accountability and acceptance among the stakeholders. Importantly, the study found that the effectiveness and better outcomes of these mechanisms is largely dependent on effective implementation. Moreover, the data also revealed five common factors, which influenced the effective implementation of