Since the field theory in physics was proposed，it has developed and been applied in many other research fields，such as ecology，economy，sociology，philosophy，psychology，and so on. Field theory is also helpful for the research of risk analysis and assessment in the realm of environmental science. According to the theory of physical field，the conception of risk field in the environmental science is introduced at the first part. Then combined with basic characteristics of risk in the environmental science，four key dimensions of risk field including hazard，type of impact，intensity of impact and type of damage are developed and analyzed in details. At the third part，two theoretical themes of risk field in the environmental science are introduced and discussed. One of them is about the research of conceptual framework of risk field and risk overlaying，and the others are the key problems about risk field in the environmental science，such as the relationship of vulnerability and risk，the interaction of perception field and risk field. It is found that the theory of risk field can provide a systemic and spatial convergence of different concepts，such as probability，loss，vulnerability and risk perception. At the same time，the theory of risk field can contribute to explore a new way of risk assessment and risk characterization，especially for the challenges for vulnerability assessment and reduction actions. In conclusion，risk field within the realm of environmental science is a valuable theory and has a wide application with good prospects.