The invention provides a method for immobilizing 
phosphatidase A1. The method is improved on the technical basis of cross-linked 
enzyme aggregates and comprises the steps of: preparing free 
phosphatidase A1 into cross-linked 
phosphatidase aggregates; and then entrapping the obtained cross-linked phosphatidase aggregates to obtain immobilized phosphatidase A1. The influences of concentration of a phosphatidase liquid, saturation degree of a precipitating agent, 
precipitation Ph value, 
precipitation time, concentration of a cross-linking agent, cross-linking time, concentration of 
sodium alginate, concentration of 
calcium ions and other different immobilizing conditions on the immobilizing efficiency and the 
catalytic effect of the phosphatidase are researched, and the enzymology nature of an immobilized phosphatidase membrane is discussed. The 
advantage of immobilizing the phosphatidase by adopting the method for entrapping and cross-linking aggregates is further explained through an SEM (
Scanning Electron Microscope) image of the immobilized phosphatidase membrane. The phosphatidase is immobilized by utilizing the excellent 
chemical stability, 
mechanical property and other properties of the entrapped and cross-linked phosphatidase aggregates, the activity and the stability of the phosphatidase in a 
reaction system are improved, the activity and the selectivity of the phosphatidase are adjusted and controlled, so as to be favorable for the 
recovery of the phosphatidase and the maintenance of higher activity 
recovery rate of the phosphatidase; and the activity 
recovery rate of the finally obtained immobilized phosphatidase is 80.2 percent, and the relative activity of the phosphatidase after being repeatedly used for seven times is kept at 65 percent above.