The work aims to review and analyze the research progress of key technologies in the preparation phase of airdrop without parachute in foreign countries, so as to promote the systematic development of airdrop without parachute technology and improve China's airdrop guarantee capability. By combing and analyzing the relevant literature, the development status of foreign environmental monitoring, precision drop and UAV (unmanned aerial vehicles) autonomous planning technology was discussed in detail, and the development trend was predicted on this basis. The foreign technology in the preparation phase of airdrop without parachute was unfolded with the precision of placement as the core, including the detection technology, monitoring technology, guidance technology and algorithmic model related to the environmental impact confrontation, prediction and identification of the airdrop site, and autonomous planning of the route. The future development trend of airdrop without parachute preparation phase technology is to focus on micro-environmental monitoring and sensing technology, intelligent processing of real-time data, focusing on navigation and guidance control technology to ensure precise and controllable material delivery, anchoring intelligent flight control technology, developing autonomous delivery of UAV swarms as well as accelerating the launch of UAV precision delivery platforms, which will help to promote the development of airdrop without parachute in China.