Identifying the characteristics of an ideal system in nature and comparing it with existing real system in a given area for possible improvement is one of the research methods in research methodology. While comparing the ideal system characteristics with existing/real system characteristics the research gap can be determined and further research can be carried out to improve the real-world system. The four basic problems still existing in the society worldwide are related to nutritious food, drinking water, renewable energy, and comfortable health. In this paper, we have studied the characteristics of the ideal water purifier, a hypothetical system used to convert contaminated water into pure water to solve drinking and irrigation water problems. The characteristics of the ideal water purifier system are classified and discussed under four categories as input characteristics, system requirements, Output characteristics, and environmental characteristics. Further, the possibilities of realizing such a system using nanotechnology are also discussed. Nanotechnology is emerging as a multi-disciplinary new frontier of Science & Technology expected to solve many major problems/needs of the mankind of the society which include supply of abundant potable drinking water, pure water for agriculture and plantations, availability of nutritious food for everybody, uninterrupted green energy for society, and comfortable health for everybody. The paper discusses the possibility of using nanotechnology to realize the ideal water purifier using nanotechnology and also the advantages, benefits, constraints, and disadvantages of such technology to improve such system towards the ideal system. New Knowledge Created/New Analysis & Interpretation : The paper created new knowledge on the concept and characteristics of ideal water purifier, and analysed and interpreted the possibility of realizing it using nanotechnology.