The invention discloses a raindrop field external load estimation method in a parachute landing process. The method comprises a step of determining a micro characteristic amount of main raindrops according to an actually measured precipitation raindrop spectra, a step of determining different working conditions according to an aerodynamic shape, fabric tension of different parts and oblique angles in a parachute steady drop process, using the high speed camera technology to capture a whole process that droplets strike a canopy under different working conditions, and obtaining a needed time that the droplets are deformed to maximum flat states for a first time and speeds in a vertical direction through post image data processing, a step of estimating raindrop impact under the working conditions according to the theorem of momentum, and a step of calculating an external load of a raindrop field to the canopy according to a raindrop surface density in the raindrop spectra and the impact in the above different working conditions. According to the method, a basis can be provided for parachute optimization design and parachute opening failure prevention in a rainstorm environment.