To address the systemic challenges in the construction industry regarding efficiency, quality, safety, and sustainable development, this paper proposes and systematically elaborates on a smart construction technology system that deeply integrates digitalization, intelligence, industrialization, and greenification, namely the DIIG system, based on twenty-three years of engineering practice. This study first traces the three-stage evolution of the system from "special process breakthrough" to "system integration innovation" and ultimately to "industry empowerment paradigm". Subsequently, it innovatively constructs a three-tier driving architecture model consisting of the "basic technology layer (foundation), system integration layer (guarantee), and frontier exploration layer (leadership)", and details the core technical composition and innovation highlights of each layer. The system has been comprehensively validated in dozens of major projects covering six typical scenarios: national emergency response, super high-rise landmarks, international cultural tourism, ecologically sensitive areas, urban renewal, and complex public buildings. Empirical data analysis shows that applying the system can reduce the average project duration by 25%-40%, lower costs by 15%-30%, decrease construction waste by 45%-70%, and achieve zero accidents in major risk operations. The achievements of the system have been solidified through intellectual property rights achieved through national engineering awards, authorized invention patents, industry/local standards, and a series of academic papers. Finally, this paper discusses the future evolution path of the system towards the Internet of Construction Industry, human-machine collaborative construction, zero-carbon buildings, and collaborative ecosystem construction of industry, academia, and research. The research indicates that the DIIG system provides a logically consistent, comprehensively validated, and quantitatively beneficial integrated solution for the systematic transformation and upgrading of the construction industry.