The invention discloses a method for producing a silicon-based ceramic core for an aircraft engine blade. The method comprises the steps of: producing the complex ceramic core through hot injection molding by utilizing three high-purity silica powders with different particle sizes as raw materials, the high-purity silica powder in large particle size as a framework, the high-purity silica powder in small particle size as sintering additives, paraffin and beewax as plasticizers, and oleic acid as a surface active agent, carrying out low-temperature dewaxing and high-temperature roasting to themolded bisque ceramic core in a padding alumina to finally obtain the silicon-based ceramic core for the aircraft engine blade.