The effects of salinity stress on the seed germination, photosynthesis, forming and shedding trendence of squares and bolls, and other agronomic characteristics and fiber quality of upland cotton (G.hirsutum L.) was carried out systematacially in this paper, using two salt-tolerant and one salt-sensitive cultivars as materials. Other characters such as the variation in ingredients and contents of chlorophyll in upland cotton leaves, and the distribution of Na+, K+ and Ca2+ within the plant parts of upland c...