Because of the large number of students and textbooks at Korea National Open University (KNOU), no study has been conducted to evaluate the quality and content of textbooks for more than 30 years. We developed an evaluation method for textbooks that was appropriate for a distance learning university with so many students. The objective of this study was to report the first term results of the textbook evaluation method. 382 textbooks developed by professors of KNOU from 20 departments were evaluated. The evaluation method was composed of three consecutive steps. In the first step, all students who received a grade higher than C+ (39,449 students in the first term and 47,227 students in the second term) were invited to respond to the evaluation sheets, which were sent to them by e-mail. The response rate by department ranged from 31.5 % to 57.3 % in the first term and 26.9 % to 53.9 % in the second term, which was large enough to represent the student population. All students who responded to the questionnaire were provided with a chance to win a prize. This seemed to encourage students to participate. Forty textbooks (two textbooks per department x 20 departments) were screened by student evaluators and thus step two began. External adjunct professors, using these 40 textbooks in the regional study centers of KNOU, were responsible for the second step of the evaluation. Two external adjunct professors per textbook were randomly selected and asked to evaluate the textbook using the same evaluation sheets as the students. A correlation test indicated that the evaluation scores by students in the first step, and adjunct professors in the second step, were not significantly different (r= 0.534 in the first term and r=0.662 in the second term). This result proved that students could fairly evaluate the textbooks. Finally, The Textbook Publication Committees (TPC) monitored each step in the evaluation process to ensure that they were appropriately conducted, and then selected the four best textbooks(20 books in the second term) on the basis of score and qualitative judgment. This study concluded that the KNOU evaluation system for textbooks could be applied to distant or open universities with tens of thousands of students.