We compare the Korean ancient calendar with the Western standard calendar from the period of Three Kingdoms (B.C. 57) to the end of Joseon dynasty (A.D. 1910). We found the necessary astronomical data and calendaric informations in Goryeosa, Joseon Wangjo Sillok, other history books. Most of the lunisolar are converted to the solar dates straightforwardly. We identified and verified some unclear data with solar eclipse data, historical events, the order investigation of 60 cycle, lunar phase calculation and Chinese documents. We find that the resulting tables are somewhat different from Chinese and Japanese ones. We also calculate the solar calendar and lunisolar calendar during 1900-2100 with the DE200 package and the DE406 package. With these results we construct the database system for the period from A.D. 918 to A.D. 2050. The database for the period of three Kingdoms and after A.D. 2050 will be added later.