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Kalidium caspicum, a halophytic shrub in the family Chenopodiaceae, is native to the inland salt deserts of Xinjiang. The effects of light, temperature and NaCl on seed germination and germination recovery were determined. With increased exposure to light, seed germination gradually decreased. The sequence in which seeds were exposed to light also influenced germination. The optimal temperature for germination was 25 to 30 degrees C. An increase in NaCl concentration progressively inhibited seed germination, with the critical salinity tolerance for seed germination 198mmol.L(-1)NaCl, and the ultimate salinity tolerance is 278mmol.L(-1)NaCl. Seeds were not affected by ion toxicity as evidenced by high germination recovery percentage and pink embryos of ungerminated seeds in solution of 2, 3, 5-triphenyl-2H-tetrazolium chloride (TTC). At high temperature (35 degrees C), some seeds did not recover germination and entered second dormancy in different NaCl solution. This phenomena indicates that exposure to high temperatures prevents germination in saline soils. The "cautious" strategy allows seeds of K. caspicum to avoid injury from salt and may play an important role in germination under desert conditions.