In order to construct the fundamental theory of macrosecurisafetyology (which combines the meanings of security & safety science for the large-scale issues), combined methods of literature review, data statistics, logical deduction and model analysis, etc. were used in this investigation. First, the research process and characteristics on the relevant theory of macrosecurisafety (which means the integrated security & safety for the large-scale issues) in the past decade were reviewed. Then, definitions, connotation, and characteristics of macrosecurisafety were given from multi perspectives, and a group of the basic concepts and their systems of macrosecurisafetyology were put forward. The disciplinary group that constitutes macrosecurisafetyology was built, and a research paradigm and principles of macrosecurisafetyology were summarized. Two macrosecurisafety models and their related definitions were built according to two scenarios. The research results clarify the scope and identification criteria of macrosecurisafety, extract 10 sets of core concept groups supporting 10 macrosecurisafetyology subjects, including macrosecurisafety state studies, macrosecurisafety meta principle studies, macrosecurisafety internal cause studies, macrosecurisafety system studies, macrosecurisafety natural disaster studies, macrosecurisafety man-made disaster studies, macrosecurisafety external cause studies, macrosecurisafety prevention and control studies, macrosecurisafety comprehensive studies, and macrosecurisafety marginal studies, providing their definitions and scopes for these macrosecurisafetyology subjects, form a research paradigm and classification for macrosecurisafetyology principles, and obtain a modeling method and two typical models for macrosecurisafetyology. The above results play an important role in consolidating the foundation of macrosecurisafetyology.