The lack of fresh water resources is attracting concern worldwide. Recently, to address this global issue, researchers proposed the heat localization concept for interfacial solar seawater desalination in 2014. Since then, interfacial solar steam generation (ISSG) devices have attracted much attention, due to their potential for achieving highly enhanced optical‐thermal conversion through a single interface as compared with traditional solar seawater desalination. To date, the promising prospect of ISSG systems in seawater desalination has stimulated the rapid development of solar desalination technology based on heat localization. To comprehensively recognize ISSG devices and acquire more insights into their design associated with biological relevance, efficiency improvement, and applications, this review summarizes the progresses and prospects of ISSG devices in relation to the evolution of advanced materials, the engineering architecture, the collaborative application, and the current challenges.