Abstract: Combining natural environmental factors such as light, temperature, strong winds, and soil in the Seni district of Nagqu city,this study explores the photosynthetic characteristics and environmental limiting factors of plants under harsh environmental conditions in the high cold and high altitude areas of Nagqu city. This results in insufficient accumulated temperature and short growth period during the plant growth season, coupled with frequent occurrence of strong winds and strong noon light radiation throughout the year,resulting in low photosynthetic efficiency and limited photosynthetic products of urban greening plants, As a result, the ability of plants to resist the high cold and drought in Nagqu is low and survival is difficult. Suggestion for local greening construction in terms of tree species selection, planting management, etc. was proposed.