To further transform and utilize fields characterized by the medium-low productivity at high altitude areas of Sakya County, the production performance evaluation test of 6 oat cultivars (Avena sativa) was conducted. 18 agronomic traits of experimental varieties were evaluated by principal component analysis (PCA) in this research. The purpose of our study was to screen out oat varieties with high production performance, and at the same time, it would provide reference to the development of vegetative agriculture in this area. The results showed that among the six varieties (except ‘Qinghai 444’) were all in the milk-ripening stage, but only ‘Qinghai 444’ could enter the wax-ripening stage. Then the average height of ‘Qinghai 444’ and ‘Qingyin No.1’ were both more than 130 cm, and which was significantly higher than the other varieties (P < 0.05). The first stem node, the second stem node and the leaf length of ‘Qingyin No.1’ were the largest. The first stem node was significantly different from other cultivars except ‘Sweet Oat’ (P < 0.05) and the second stem node was significantly different from ‘Jiayan No.2’ and ‘Sweet Oat’ (P < 0.05). Furthermore, the leaf length was significantly higher than the other 5 cultivars (P<0.05). ‘Qinghai 444’ had the coarser stem and ‘Sweet Oat’ had the highest leaf-stem ratio, and their roots were relatively developed. ‘Qingyin No.2’ had the highest fresh grass yield and hay yield, which were 49 850.21 and 13 928.25 kg·hm^-2, respectively. But there was no significant difference in hay yield among 6 cultivars. Based on the comprehensive score of principal components, ‘Qingyin No.1’ and ‘Qingyin No.2’ were the most suitable oat varieties for planting in fields characterized by low-medium productivity at the high altitude area of Sakya County.