With the development of next-generation communications and equipment towards wider bandwidth and higher accuracy, millimeter wave and terahertz band has become the research focus of microwave technology. Transmit power is a significant figure of terahertz system, which directly determines the operating distance. Millimeter wave and terahertz solid-state power devices reveal great advances recently, and the engineering realization of terahertz solid-state power amplifiers at home and abroad is promoted. In this article, the international research status of millimeter wave terahertz power combining technology and solid-state power amplifier is introduced, and the latest research progresses of solid-state power amplifier modules based on radial combining, rectangular waveguide combining and silicon waveguide combining at W and G band in China, especially in Nanjing Electronic Devices Institute, are concluded.