Wooden cultural heritages of Korea have been destroyed by fire in many cases. As a result, a number of methods to protect wooden cultural properties against fire were introduced. A way of protecting wooden cultural properties installations of fire equipments such as sprinkler, fire alarm system, or fire extinguisher. Another way of protecting wooden cultural properties is to treat them with flame retardants for their safety. Development of a very effective flame retardant with a good performance without affecting danchung and wood quality is required. At the same time, methods of evaluating flame retardant treated woods should be devised to assess their efficacy. In this study, combustion characteristics using cone-calorimeter, limit oxygen index, moisture absorption, iron corrosive and weathering were analyzed to evaluate the flame resistance efficacy and performance of flame retardants treated woods. The evaluation methods of flame retardants for wooden cultural heritage were suggested.