Discussions on how to perform tasks at disaster sites are actively conducted, but there is little debate on important issues such as how to deliver robots to disaster sites. To drop a humanoid robot with a parachute from an airplane is one of the promising ways of delivering robots. In this paper, the behavior of falling during parachute landing is modeled with an inverted pendulum model and the validity of the model is verified by the drop tests with a small single-legged robot. In addition, it was found that when the robot was dropped with a half-sitting posture, the impact acceleration is reduced. Based on this result, a parachute landing fall motion is designed and is succeeded in reducing the impact acceleration to 41%.