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Based on the analysis of metabolic pathway Streptococcous zooepidemicus for hyaluronic acid (HA) synthesis, nucleotide,especially uracil, was considered to be important to cell growth and metabolism. When 0.005 g·L-1 uracil added in the media in which yeast extract as complex nitrogen source, cell growth and HA production were increased by 32 % and 34 % respectively. From analysis of amino acid in fermentation process, it was show that arginine(Arg) was needed for cell metabolism,and concentration of free Arg maintained at 0 g·L-1 in fermentation process, which was proposed to limit cell growth and HA production. By shake-flask experiment HA concentration reached 0.510 g·L-1 whene 0.06 g·L-1 Arg added,in the fermentation with 2.5 L fermentor, when uracil 0.005 g·L-1 and Arg 0.06 g·L-1 were added, the rate of cell growth increased, maximum of specific growth rate, concentration of HA and HA molecular weight reached 0.67 h-1 ,5.2 g·L-1 and 2.15×106 Da from 0.54 h-1,4.2 g·L-1,2.0×106 Da,respectively.