In order to determine whether it is appropriate to store cultural objects affected by tsunami,classroom environment in a school,which had been closed at the time of disaster, was investigated. The classrooms were used for temporary storage of cultural objects evacuated from the area in Fukushima Prefecture restricted by the Fukushima Daiichi Nuclear Power Plant disaster.Some cultural objects affected by the tsunami following the 2011 off the Pacific coast of Tohaku Earthquake in Minamisoma city were also stored there. Before transporting the cultural objects, the room windows were closed with styrofoam to reinforce light shielding and heat insulation.Temperature,relative humidity and illuminance in the classrooms were measured from February to August 2015.Temperature of the rooms having windows sealed with styrofoam gradually changed from about 7℃ to 35℃.Relative humidity in classrooms where dehumidifiers were installed was controlled under 60% r.h. in humid summer season. lluminance of the rooms having windows sealed with styrofoam did not exceed 100 lux. In rooms where light shielding and heat insulation were not reinforced, illuminance was high and variation in temperature and humidity was large every day.Thus,it was made clear that reinforced light shielding and heat insulation are essential in order to use a closed school as a storage.