Facing the urgent needs for meteorological and climate prediction and atmospheric environment monitoring, the use of active spaceborne instruments to detect global clouds and aerosols has become a rapidly developing research field. Compared with passive remote sensing technologies, active instruments could obtain profiles of cloud and aerosol parameters, which play an important role in improving weather and climate models. In this paper, the scientific requirements for cloud and aerosol remote sensing are discussed out. First, the application and quantitative demands of number models for the cloud and aerosol measurements for models are introduced from the perspective of radar data application. Further, the requirements for joint observation of clouds and aerosols, and the detection characteristics of spaceborne microwave lidar radar are analyzed. In addition, the planned mission for spaceborne lidar and millimeter-wave radar for cloud and aerosol remote sensing including instrument specifications and product designs are reviewed. Finally, the future development of this field is also presented.