In recent years, a number of institutions, local governments, and companies around the world have been working to resolve issues related to the 17 goals to realize the Sustainable Development Goals (SDGs.) The SDGs aim to realize a society where “No one will be left behind” and the environment of the earth and society is maintained in the form not to damage the future generations’ needs. As in other sectors, the SDGs for ‘information’ are attracting people’s attention. It is expected that the spread of Information and Communication Technology (ICT) plays a vital role in the formation of the infrastructure for various industries and brings about technological innovations. Besides that, on a worldwide scale, people also take full advantage of Information Technology (IT) to build infrastructure and develop newer technologies to create sustainable industries. Hereupon, this paper defines “information environment,” and explains its significance today to achieve a sustainable information environment based on the goals of SDGs. These days, we use tools such as social networking services and mobile phones to form our culture in an environment with overwhelming abundance of IT. ‘SDGs Informatics’ is the informatics to realize a sustainable information environment. It is the study of designing theories and methods that form the basis for the sustainability of the information environment. The “information environment” defined in this study consists of three elements: ‘environment,’ ‘information tools,’ and ‘information culture”. A foundation is the ‘information infrastructure’ called ‘environment.’ On top of this infrastructure, there are ‘information tools,’ which are platforms for utilizing the ‘environment’ and they works as the method to access to the ‘environment.’ The combination of these two elements gives birth to ‘information culture.’ The ‘information culture’ is created simultaneously when people use ‘information tools’ to achieve certain objectives, and human actions and interactions are essentially involved in it. The above three-tiered elements are integrally referred to as “information environment” in this study. A specific example of an ‘environment’ is the ‘Internet’ as a mean of communication. The ‘Internet,’ as ‘environment’ is used to achieve the goal of ‘communicating with others,’ and information tools such as ‘mobile phones and smartphones’ are used as a mean of accessing to the Internet. Then, a culture of ‘digital communication’ such as ‘e-mail’ and ‘social networking services’ is invented to achieve the objective. By breaking down the “information environment” into ‘environment,’ ‘tools,’ and ‘culture,’ it becomes possible to visualize the elements that are currently ‘sustainable’ or ‘unsustainable.’ ‘The conditions surrounding information’ is becoming harder to continuously maintain due to rapid changes in devices and significant platform updates. A gap has emerged between ‘those who are able to respond to updates and those who belong to environments that allow them to do so’ and ‘the rest of the population.’ We focus on this issue and aim to realize a “sustainable information environment”. Achieving a sustainable information environment means that what is possible under the existing information environment can be continuously used in any changing environment or with any technology. Through this research, we propose to continuously use the surrounding environment, information tools, and information culture.