Abstract: The Pinellia ternatat was used as the test material, and two treatment groups of complete nutrition and low phosphorus stress were set up by indoor pot experiment.The effects of low phosphorus stress on growth, total chlorophyll, soluble sugar, free amino acid, soluble protein, β-sitosterol, total flavone and organic acid of Pinellia ternatat were studied, in order to understand the response substances of Pinellia ternatat under low phosphorus stress and better deal with the problem of phosphorus deficiency in actual production.The results showed that the quality of Pinellia ternatat was significantly affected by low phosphorus stress.The contents of leaf length, leaf width, leaf weight, total chlorophyll, free amino acid, soluble protein and total flavonoids decreased, while the contents of tuber weight, soluble sugar, β-sitosterol and organic acid increased.Among them, soluble sugar, total chlorophyll and organic acid may be the main indexes of quality difference of Pinellia ternatat under low phosphorus stress.