OUSL Internal Quality Assurance Unit’s (IQAU) mission is to establish and implement monitoring mechanisms to maintain quality standards in all academic and operational activities, so as to ensure learners get the best out of the Higher educational programmes, offered through Open Distance learning (ODL). It is also in place to ensure that other stakeholders, both internal and external, benefit from OUSL's products and services.

Initially quality assurance activities of the university were carried out by Senate appointed Quality Assurance (QA) committee in 2004. Its main role was to facilitate external reviews conducted by the UGC for all universities in Sri Lanka. A remarkable achievement of this QA committee was its own initiatives in drawing up a quality assurance frame work for distance mode higher education institutes and programmes of study , which was internationalized in 2009 and is currently being used by all distance Higher educational institutes worldwide.

In 2012, the membership of QA Committee was increased to include members of the Senior management and other administrative officers of the university by forming the Internal Quality Assurance Unit (IQAU). This was because we realized that a collective effort on continuous monitoring and internal quality assurance is an essential requirement to provide a high standard education for the learners of the OUSL. At present OUSL strives to achieve its mission by adopting a decentralized approach to quality assurance by having quality assurance committees/cells in every faculty, CETME and in administrative divisions.