The assistive devices that applies advanced technology such as artificial intelligence(AI), internet of things(IoT), and robot, are expected to support the independent life of the elderly and disabled people, and to lower the physical burden of caregivers. The COVID-19 pandemic has accelerated the transition to contactless welfare service delivery. Thus, this research aims to develop  proper strategies for welfare service applying high-tech assistive devices in Seoul. The high-tech assistive devices were developed at various levels from prototype to commercial products, and the degree of commercialization was different according to the institutional context by the countries. IoT sensors for monitoring and AI robot for emotional support and monitoring were provided the most to the elderly people living alone in the form of pilot project in Seoul. This research suggests four directions to develop advanced welfare service applying high-tech assistive devices in Seoul. Firstly, the development and provision of welfare services using high-tech assistive devices should be user-centered. Legal and institutional foundation for utilization of high-tech assistive devices should be established, and short- and long-term strategy for digital transition of welfare services in Seoul should be made. Based on the strategic plan, the assistive device delivery system should be integrated. Lastly, it will be necessary to expand the digital education program for the elderly, the disabled, and the caregivers.