Porous graphene, as an emerging carbon nanomaterial, possesses a range of distinctive physical and chemical properties, such as its lightweight nature and high specific surface area. These properties hold great promise for numerous applications in the fields of physics, chemistry, materials science, energy, and information science, among others. Consequently, research and exploration in this area have gained global attention. Nevertheless, the conventional methods for fabricating porous graphene and two-dimensional planar graphene are complex, and obtaining specific patterns with precise graphene areas presents a challenge. In recent years, laser-induced graphene (LIG) has emerged as a promising technology that offers efficient fabrication of graphene and precise control over patterned structures. This technology significantly reduces production costs compared to traditional processing methods. Consequently, scholars have become increasingly interested in LIG and have made numerous efforts to explore its applications in various fields, including energy, information, and environmental sciences. This review systematically compares different synthesis methods of LIG, summarizes and analyzes the effects of laser processing parameters, laser types, precursor materials, process atmospheres, and other factors on the performance of LIG. In addition, the formation mechanism of LIG is discussed over experimental observation and theoretical simulation, and the structure evolution both in micro- and atomic levels are also explored. Furthermore, this review comprehensively covers recent applications of LIG across a wide range of fields, encompassing various sensors, energy devices, environmental protection techniques, and terahertz modulation equipment. Finally, insights are provided into the future directions and trends of this research technology.