This study analyses the questions addressed to the collaborative digital reference service run by the National Library of Korea. The data consist of 661 question entries to the 'Ask a Librarian' service during first 6 months in 2014. Each entry includes average 1.17 questions, and 77.82% of the total questions are real reference in nature. Questions are analyzed by classification division, context of the questioner, desired end product, activities of librarians, and the resources used to respond them. Each category is subdivided and analyzed in detail. Results revealed interesting findings and problems, and suggestions for further endeavor are provided.