This study was made to investigated the effect of pulping process conditions such as wastepaper blendings, temperature, chemical blendings on the deinked pulp. Design of experiments was used to find the optimum conditions such as wastepaper blendings temperature, chemical blendings on the deinked pulp And one of the statistical analysis technique, analysis of varience and multiple comparison was used to select the best combination and determined the estimators and confidence intervals for brightness and strength. Conditions of Na₂SiO₃ 2.0%, H₂O₂ 0.5%, wastepaper blendings(AONP:KONP:OMG=40:30:30%) gave the highest brightness estimator 50.5% and 90% confidence interval (49.0, 52.0), and conditions of H₂O₂ 0.5%, pulping temperature 50℃ gave the highest tensile index estimator 35.7N·m/g and 90% confidence interval (34.6, 36.6). Also, conditions of surfactant 0.1%, pulping temperature 50% gave the highest burst index estimator 0.129kPa·m²/g and 90% confidence interval (0.125, 0.133).