The invention discloses an asymmetric diffraction measurement method for content of residual austenite in steel. The asymmetric diffraction measurement method comprises the following steps: firstly, measuring a diffraction peak position; then, sequentially rotating a detector to the diffraction peak position and stopping; then independently swinging a test sample along a 1theta axis and stopping step by step; taking a normal of a test surface of the test sample as the axis and rotating for 360 degrees, and recording the integrated intensity of X-ray diffraction rays; similarly, after a background of background intensity I of a diffraction peak is measured, obtaining X-ray diffraction ray accumulated net intensity of the diffraction peak is obtained; substituting the X-ray diffraction ray accumulated net intensity of five diffraction peaks under the same inclined angle on the 1theta axis of the test sample as one group of numerical value into a formula of Black Metallurgical Industry Standards YB/T5338-2006, so that the content of the austenite in the test sample under a certain inclined angle of the 1theta axis is calculated and an average value is the content of the austenite in the test sample. With the adoption of the method provided by the invention, the content of the austenite in a steel material containing a texture can be accurately obtained, and further processing and production of the steel material are facilitated.