Recently, the Earth Science Department’s Fifth Division of Earth Science (Atmospheric Sciences Discipline) of the National Natural Science Foundation of China (NSFC) has improved the discipline structure and adjusted the fund application code. Among them, the addition of the secondary application code D0508 for “planetary atmospheres” is remarkable. The major purpose of adding this application code is to promote the research of planetary atmospheres, expand the planetary atmospheres research team, and continuously support the development of the entire atmospheric sciences in China. This article explains the settings of three research areas and 24 keywords under this application code and explains the specific reasons and relevant connections for the settings. Through this introduction, fund applicants may better understand the logic of setting these research directions and keywords and lay a good foundation for a more accurate selection of research directions and keywords in the fund application processes.