Nieuguling, 3 km south of Hongmao, Hsinchu County, is the sole habitat of Quercus aliena Blume in Taiwan. The paper is attempted to study the forest structure and dynamics of the species in the forest in which Q. aliena inhabits by setting a permanent quadrate, and to infer the possible origin of Q. aliena in Taiwan based on DNA data. A total of 0.09 hectare quadrate has been set up. The paper presented the distribution of individuals of each species with DBH over 1 cm long, and described the forest structure and the distribution range of DBH of Q. aliena and its accompanied species. The trnL-trnF chloroplast DNA did not resolve the origin of Q. aliena in Taiwan, but the paper suggested future works that might be carried on for a better understanding of Q. aliena.