Ecological degradation is a critical problem faced by every country in the world. The study of restoration of degraded ecosystem has been recently considered as one of scientific issues and public focuses because drastic ecological degradation results in huge economic and ecological loss. Huangguliang small watershed of Lanxian County, located in the northwest of Shanxi province, is one of the most typical ecological frangible areas on the Loess Plateau in North China. Based on the field investigation, two-way indicator species analysis (TWINSPAN) and detrended correspondence analysis (DCA) were applied to the analysis of ecological relationships among artificial vegetation communities in Huangguliang small watershed. It was showed that: (1) One hundred-two samples located in different altitudes and aspects were classified into twelve associations by TWINSPAN and their characteristics, including distribution of dominant species and relationshaip with environmental factors, were described respectively. All results were confirmed by the two-dimensional ordination diagram of DCA. (2) The environmental variables, such as soil moisture, altitude, aspect and succession time were the major environmental factors in affecting the change and distribution of the communities. The results of DCA ordination showed that the artificial associations have their difference distribution along environmental gradient. The first two axes of DCA reflect the gradient of soil moisture, altitude, aspect and succession time of the communities. (3) The distribution patterns of dominant species were highly similar to that of the communities. With the decrease of the altitude, the association of Pinus tabulaeformis, Hippophae rhamnoides and Carex lanceolata were gradually taking place by the association of Caragana korshinskii, Carex lanceolata and Artemisia capillaris, which showed that community distribution patterns were coordinating to the zonal vegetation distribution patterns due to the decrease of elevation and soil moisture. (4) The difference of species diversity of community has main closely correlation to soil moisture, altitude, aspect and succession time, meanwhile, also has closely correlation to the habitat. Species diversity of the artificial vegetation in semi-sunny slope, semi-shadow slope, shadow slope and higher altitude area with better water supply, was much richer than that in sunny slope and lower altitude area. Meanwhile, species diversity plays an important role in the development and distribution of the artificial vegetation communities. (5) Species types and their plant pattern have an obvious interruption effect to the succession of artificial vegetation communities in Huangguliang small watershed. The restoration effects of mixed forest, such as Populus simonii+Pinus tabulaeformis, Pinus tabulaeformis+Larix principis-rupprechtii-Hippophae rhamnoides, Pinus tabulaeformis-Caragana korshinskii, Pinus tabulaeformis-Hippophae rhamnoides, etc. are much better than that of Caragana korshinskii pure forest. And human interruption could accelerate the process of succession, which has validated the previous researchers′ opinions. Moreover, Larix principis-rupprechtii is fit for growing in semi-sunny, semi-shadow slope, shadow slope at higher altitude. Populus simonii is fit for growing in valley and semi-sunny and semi-shadow slope at lower altitude, while Pinus tabulaeformis, Hippophae rhamnoides and Caragana korshinskii with strong ecological adaptability are fit for growing in any of altitude and aspect in Huangguliang small watershed. (6) The course of artificial vegetation community succession in Huangguliang small watershed follows the succession law of local zonal vegetation. With the community succession, the wild plants have continuously invaded and the canopy densities of Pinus tabulaeformis, Larix principis-rupprechtii and Populus simonii etc. forests have increased. While the shrubs of Hippophae rhamnoides and Caragana korshinskii have gradually degenerated. The forests of Pinus tabulaeformis, Larix principis-rupprechtii and Populus simonii etc. have occurred deadwoods, which are the results of self-thinning. So the effective forest management is urgently needed.