In order to optimize designing process of corrugated fiberboard boxes for agricultural products, first of all, compression strength of each liner were experimentally evaluated on the various conditions of relative humidity and analyzed by liner regression analysis. At the 66 percents of relative humidity, IK(imported kraft liner) liner board lost little of its compression strength compared to others. At the relative humidity 93 percents, KA liner board lost its compression strength only 40 percents while SK liner board lost up to 56 percents. From the result of prediction modeling of ring crush strength in various humidity conditions, R square values were ranged from 0.59 to 0.97. At 56 percents of RH or below, R square values were relatively low, but at 66 percents of RH or higher, the values were 0.85 or higher. The significance values were lower than 0.001 at every RH condition. Level of significance of experimented values was about 80 percents of predicted values and R square values were between 0.89 to 0.95.