Quality is at the heart of education, including distance education. Over the past years, quality assurance in distance education has become even more important as distance education gains popularity and faces a period of borderless e-learning. We have begun to observe the development and implementation of quality assurance policies for distance education that are different from those for on- campus education,This paper is an effort to analyze important meanings of extensive research results in interpreting, integrating and evaluating the quality of distance education, explore some selected distance education cases in developing and implementing quality assurance mechanisms at the national and institutional levels, and finally suggest some future research areas and practical guidelines for quality assurance in distance education.