Abstract: This paper presented the results of decolouring and enzymatic hydrolysis technology of P.urceolata to prepare a nutritive liquid of composite amino acids.The results showed that KMnO4 was a good decolourant for P.urceolata.The optimum hydrolysis conditions were :using combined enzymes (AS1.389 protease and trypsin,5‰ totally) at 45℃ for 4 hours and then treating with 0.2% NaOH for 2 hours.The degree of protein hydrolysis was up to 80.4% ,and the transformation ratio of amino acids was 39.6%.