The invention relates to a preparation method of an amino polyether organic 
silicon compounded antifoaming agent. The method comprises the following technological steps: (1) adding 
allyl glycidyl ether and a 
platinum catalyst into a container, heating under stirring and 
reflux condensing conditions in the protection of N2, adding a 
toluene solution of 
hydrogen-containing 
silicone oil when the temperature rises to a certain level, after the reactions, removing the 
solvent and substances with low boiling points in a 
rotary evaporator, and 
drying so as to obtain 
epoxy modified 
silicone oil; (2) adding the 
epoxy modified 
silicon oil obtained in the step (1) and an 
ethanol solution of polyether amine into a container, heating under stirring, carrying out reactions under the 
reflux condensing conditions in the protection of N2, after the reactions, removing 
ethanol in a 
rotary evaporator, and 
drying so as to obtain amino polyether organic 
silicon; (3) compounding the amino polyether organic silicon obtained in the step (2) with a certain amount of 
silicone cream, a mixed emulsifier, and a 
thickening agent to prepare the amino polyether organic silicon compounded antifoaming agent. In the provided method, amino polyether organic silicon is prepared through a silicon-
hydrogen addition / 
amination reaction and then is compounded with an emulsifier, a 
thickening agent, and silicon cream so as to prepare the amino polyether organic silicon compounded antifoaming agent, which can be dissolved in water quickly, has the advantages of excellent 
heat resistance, 
acid resistance, alkali resistance, and antifoaming property, and has the same performance as that of antifoaming agents in the market.