The invention discloses a method for detecting the cooking degree of an egg based on light transmission. The method comprises the following steps: firstly collecting the light-transmission picture ofthe egg; then calculating the central temperature of the egg based on the gray level of an egg center in the picture; and finally determining the cooking degree of the egg according to the central temperature of the egg. According to the invention, the central temperature of egg yolk is utilized to define the cooking degree of the egg, so the cooking degree of the egg can be more accurately reflected; the method is a non-invasive and quantitative method for detecting the cooking degree of the egg; compared with traditional qualitative analysis methods like time analysis methods and illumination analysis, the method provided by the invention is more accurate and reliable in provided information about the cooking degree of the egg and meets people's needs for various aspects such as taste, color and nutritional value.