Great challenges in the context of the realization of the rights of future generations predetermined investment in the environmental sphere for sustainable development, which entails the development of convergent technologies. Convergent technologies categorically form a conceptual synthesis of NBIC-technologies, nature-like and other technologies, the application of which marks a technological revolution in the context of greening activities. Convergent technologies are implemented in accordance with the current legislation and provided by LegalTech. LegalTech of convergent technologies is a synthesis of services that optimize convergent technologies and solutions that enable the implementation of convergent technologies for sustainable development, environmental protection, harmonization of the technosphere, nature and society in the algorithm set by big challenges and nature. The authors analyze and characterize the concepts of sustainable development, «green» investment, investment in the environmental sphere, Legaltech, LegalTech convergent technologies, as well as analyze foreign experience, substantiate the Russian specifics of investment in Legaltech convergent technologies for sustainable development. The results of the study demonstrate the opportunities and prospects of scientific, regulatory and law enforcement practice of investing in LegalTech convergent technologies.