Abstract: Arabinogalactan was extracted from processing residue of Larix gmelinii Rupr. wood as raw material. Water was used as solvent, assisted by microwave irradiation. In the experiments, parameters affecting extraction of arabinogalactan, namely: microwave power, irradiation time, wood flour granularity, the ratio of liquid to material were analysed with orthogonal experiment of microwave-assisted extraction. The optimum parameters were obtained as follows: microwave power 210 W, irradiation time 35 min, ratio of liquid to material 1:35, wood flour granularity 0.2-0.3 mm. The extract yield of arabinogalactan was 17.47%, which was 1.6% higher than traditional water extraction, with time only 1/10 of the latter. The products obtained from both extraction methods were identical in chemical structure by IR analyses. The impurity content of raw arabinogalactan by microwave extraction was lower than that by traditional water extraction. The experiment results showed that microwave-assisted extraction is superior to traditional water extraction for extraction of arabinogalactan from Larix gmelinii R. wood.