Abstract: In this study, a large number of administrative villages belonging to three typical townships (Nagqu, Luoma and Kongma) near Nagqu Prefecture in northern Tibet were investigated by using semi-structured interviews in participatory rural assessment. The ecological problems of grassland were studied from the perspective of humanistic factors, and the specific ecological concept and production mode of herdsmen were excavated and analyzed. We aimed to provide a reference for the implementation of harmonious coexistence in ecological system of grassland-livestock-people, evaluation on vulnerability of ecological environment, and establishment of grassland ecological protection measures in a targeted way. Results showed that 70% of the investigated herdsmen considered that the grassland quality was reduced and 65.0% of the investigated herdsmen considered rodent-insect harms as the leading cause of grassland degradation;in respect of cognition on control countermeasures of grassland degradation, 21.7% of the investigated herdsmen considered that the grazing pressure (number of grazing cattle and sheep) was expected to be reduced.