Abstract: The effects of main factors. invoving pH value, lightshine, temperature, oxygen and microbe,and the interaction between them were investigated for the stability of chlorophyll in fresh spinach juice, The results show that to remarkable character of all effect factors on stability of chlorophyll,lightshine occupies first place, microbe and oxygen come second, while pH value and temperture are not notable. The interaction between microbe and oxygen is intense, and the interaction between the other factors may be negligible.