Abstract: The rooting ability of ten varieties (types) of Catalpa spp. was studied. The untignified branch cutting techaique for ‘Yuanjicbangguo’, which was considered as a valuable type to be spread, was analyzed in this paper, h was found that the rooting ability of ’Zi ’and ’Hut’, whose rooting rate reached 80%, was better than olher trpes. ’Nanyaug’, ’Yuanjichangguo’ and ’Yu’-l also had hetter rooting capacity because their rooting rate surpassed 50% The orthogonal test for ’Yuanjiehangguo’ indicated that the impacting of five factors on vooting rate had a seqaence as follows: hormane density>hormone type>cutting coarseness>process time>the cutting length. And the optimal combination for ’YuanJichangguo’ was that 1500mg/kg ABT 6powder was used to deal with unlignified branch for 30s, and cutting bad a length of 10-12cm, roughness of 0.3-0.6cm.