Abstract: In this paper, systematic studies on 1, 2, 3 years old young Populus bolleana Lauche with bark are conducted as regards to their wood structures, fiker characteristies and chemical compositions. Two different pulping processes are employed, and the pulping characteristics are investigated. The specific gravites of these samples with bark are in the range of 0. 34-0. 44 g ?cm-3, their content of bark 18. 55%-21. 88%, their fiber length 0. 64 - 0. 72 mm, fiber width 17. 09-19. 40 urn, length/width ratio 33~42, Runkel ratio>1. They have a high content of holocellulose (78. 07%-78. 63%) , a higher content of extractive, a higher content of ash (1. 89%-2. 24%) and a low content of lignin (20. 07%-20. 18%). They are apparently raw materials for paper making. The optimum process conditions for Kraft of two years old P. bolleana L. with bark are chosen by employing a microcomputer. The optimum regression equations for the kraft process are given in this paper. Results of the test indicate that the optimum sulfidity (all calculated as sodium oxide) is 20%, the total amount of alkali is 1 6. 5% (calculated as sodium oxide) , with the ratio of liquor to chips being 4 : 1 and the cooking time required at maximum temperature (165℃) is 90 minutes. The results of the cooking tests show that the total pulp yield is 50. 61 % and Kappa number 21. 74. The chips with bark require higher alkali (at same maximum temperature and cooking time). It has been found that AP-AQ process can also be suitable to young Populus b. L. with bark for pulping to produce bleached grade chemical pulps.