The main purpose of this research is to explore various countries experiences about developing blended learning system in distance education universities. Blended learning, as a third wave in developing learning environment, has become commonplace after the resident and e-learning environments in universities. The goal of this movement is improving learning qualities, extending the boundaries of education and decreasing educational costs. In this study, a qualitative approach and a comparative method were used. The qualitative method was used to understand the social contexts of distance education universities and comparative approach was applied to compare universities in terms of observable categories. Among 17 distance mega universities in the world, four universities, including Indirah Gandhi National Open University in India, Anadulu Open University in Turkey, Open University of China ( OUC) , and Alberta Open University in Canada were selected using purposeful sampling. The data collecting tool consisted of a checklist that was prepared with emphasis on 10 categories of social and cultural features of the countries including general situation of public and higher education, distance education, policies related to blended learning, learning management system, content development and presenting method, learning activities and resources, support system, interaction systems, teaching and assessment method, and evaluation system of learning quality. The required data were also collected through note taking procedure from sites of universities and related articles and books. For data collection and analysis, George Brody's four-step method ( Description, Interpretation, Proximity, and Comparison) was used . At first, required data was gathered from articles, university web sites, and interaction with informed people through note taking. Next, data were interpreted after continuous review with regard to university social and cultural contexts. In the third stage, data was organized and categorized based on similarity and differences and then were compared. Results showed that each four universities uses British open university framework in organizational structure. Each university included blending learning in their system based on their polices. Along with self-learning textual content, the universities started providing electronic content and designing learning activates with using ICT possibilities, while the Athabasca University emphasizes on individual and group learning activities. In each four universities, using educational TV as a learning aid is common place. Support services system in each university is Commensurate with social and cultural conditions. Online synchronous and asynchronous teaching is part of teaching activities in each university, but its quality is different. Learning assessment in different in four universities, but formative and summative evaluations are emphasized in all universities. Quality assurance system in Athabasca and OUC is based on PLAR, in Anadolu University based on the Bologna scheme, and in Indirah Gandhi, based on Council of Higher Education. In this research, for developing blended learning in Payame Noor University, a framework is provided at the end.