Cast-forging GH4096 superalloy turbine disk is a key hot end component of aero-engine because of its excellent properties such as high temperature bearing capacity, high strength, low crack growth rate, high fatigue resistance and so on. However, due to its high alloying degree, large part size and complex preparation process, it is inevitable that the composition and microstructure distribution will be uneven, which will affect the service performance of the turbine disk to a certain extent. Micro-area X-ray fluorescence spectroscopy (μ-XRF) has the advantages of high micro-resolution, fast analysis speed, simultaneous analysis of multi-elements, non-destructive and so on, so it is widely used in archaeology, geology, biology and other fields. However, there is little research on the composition distribution of large-size superalloy components, and there is no report on the quantitative distribution of composition at the original location of the material. In this experiment, by selecting suitable measuring conditions and optimizing instrument quantitative method, a new quantitative analysis method of composition distribution of cast-forging GH4096 alloy turbine disk based on microbeam X-ray fluorescence spectroscopy was established, and the in-situ statistical analysis method was introduced to analyze the quantitative statistical distribution of Cr, Co, Mo, W, Ti, Al, Nb and Ni in turbine disk. It is found that Co, Mo and Ti have obvious arc negative segregation zone from hub to flange in the central region of turbine disk thickness, while Ni and Cr have arc positive segregation zone. In addition, there is also a certain composition gradient distribution in the radial direction of the turbine disk. The contents of Co, Cr and W gradually decrease from the hub to the flange, while the contents of Mo, Ti and Nb show a gradual upward trend. After the calculation and analysis of the maximum segregation degree, statistical segregation degree and statistical fitting degree of each element, it is known that the overall segregation degree of Cr, Co, Mo, W, Ti, Nb and Ni elements in the measurement area is small, the statistical coincidence degree is large, and they have better composition uniformity within the allowable range of material element design values. The linear distribution of elements in the same test area was analyzed by spark source metal in-situ analyzer (OPA-200). The analysis results agree with those obtained by microbeam fluorescence spectra, indicating that there is temperature field distribution in large-size turbine disks during heat treatment, which leads to differences in element diffusion behavior and microstructure distribution, so there is some segregation in different parts. Through the quantitative statistical analysis of the composition distribution of the large size turbine disk, it is of great significance to evaluate the uniformity of the composition distribution of the new cast-forging deformed GH4096 superalloy turbine disk and to analyze the correlation between the preparation process and the composition and structure distribution of the significant size components.