In order to verify the feasibility and effectiveness of the remote sensing estimation method for dynamic harvest index (D-HI) based on the dynamic fraction of cumulative aboveground biomass after anthesis (D-fG) to obtain the regional spatial information of crop harvest index, the research on the regional estimation of crop harvest index was carried out, which was supported by the previous research results of sensitive band centers and their maximum band widths for crop harvest index estimation at the canopy level. Hengshui City, Hebei Province in Huang-Huai-Hai Plain of China was selected as the study area, and winter wheat was selected as the research object, and the simulated reflectance data of Sentinel-2A and its real satellite remote sensing data were used. Finally, under the guidance of optimal band information for D-HI estimation of winter wheat based on the simulated Sentinel-2A remote sensing data of different band combinations, the Sentinel-2A image data were used to obtain accurate spatial information of regional crop D-HI. The results showed that under the condition of the simulated reflectance bands of λ1(672~680nm) and λ2 (855~875nm), the D-HI estimation accuracy based on D-fG remote sensing information was the highest, the root mean square error (RMSE), normalized root mean square error (NRMSE), and mean relative error (MRE) were 0.0404, 10.83%, and 9.56%, respectively, which proved that Sentinel-2A satellite remote sensing data had certain application potential in the estimation of winter wheat harvest index. At the same time, supported by the band information of simulated remote sensing data with the highest estimation accuracy of D-HI, the RMSE, NRMSE and MRE were 0.0502, 13.81%, and 12.00%, respectively, in the overall verification of D-HI estimation at different grain filling stages and maturity stages based on red band and narrow NIR band of Sentinel-2A satellite remote sensing data. The above results indicated that the remote sensing estimation method of crop D-HI based on Sentinel-2A satellite data and the fraction of cumulative aboveground biomass after anthesis had certain feasibility and effectiveness in the acquisition of regional spatial information of D-HI, and it could provide a certain technical method reference for the accurate acquisition of crop D-HI spatial information based on multispectral satellite remote sensing data in a large region.