With the process of climate change and global change,the risk of future crop losses caused by natural disasters is increasing,which poses a great threat to global food security. The assessment of crop losses has become a hot issue in disaster risk research. The current contribution of exposure to risk has exceeded climate change 's influence,which makes it particularly important to describe and measure crop exposure in its loss risk assessment. This paper firstly focuses on the definition of crop exposure from different perspectives,and it is believed that the exposure needs to be understood by space and time dimension,which can reflect its amplification or reduction effect on disaster losses. Secondly,three kinds of spatial dimension indicators and the corresponding time dimension indicators of crop exposure are summarized. Finally,it sums up the calculation methods and models of crop range,yield,economic value and time dimension indicators,to understand the exposure connotation more systematically and comprehensively,meet the needs of disaster system complexity research and provide scientific support for quantitative risk assessment.