Chlorella ellipsoidea were cultured in "cold" media starvated with the nitrate and phsophate sources. The effects of the nitrate and phsophate starvation on the biosynthesis of phospholipid and the composition of fatty acids in chloroplasts isolated from these cells were analyzed. The syntheses of phosphatidylcholine and phosphatidylinositol in the nitrate and phosphate starvation were similarly inhibited as compared with the control but phsophatidylethanolamine synthesis in the nitrate starvation was extremely lower than that in the phosphate starvation. The major fatty acids utilized in phospholipid formation within chloroplasts were palmitic acid and linolenic aicd. However, palmitic acid and stearic acid were dominant in the condition of the nitrate starvation. The levels of palmitic acid were enhanced 3-fold than that of the control. These results suggest that the biosynthesis of phospholipid and the composition of fatty acids were affected by the nitrate and phosphate starvation in the culture media.ure media.