In order to maintain and evaluate the adequate humidity and temperature of a museum, the data of these should be periodically monitored and accumulated. For this purpose, We have designed the interpretation method of charts of the widely used thermo hydrorecorder at the museum, and developed the computer-based program (name of the program : HATH interpretation program). This method is as follows;The recording of thermo hydrorecorder(model ; Sato R-704) Input a through scanner (UMAX type), and was transformed into numerical value and was processed the statistics by HATH interpretation program. Output can be present the numerical value and the graph which are classified by a day, a month, and a year. By this method, the humidity and temperature data which were taken from 12points in the exhibition case, storage and outdoor of the Ho-Am art Museum in 1995 were processed. At the results, its ability for fast processing, management and analysis of the data was proved to be excellent.