Recently, energy harvesting technologies have attracted much attention for realization of energy saving society, greenhouse gas reduction, and independent power supply for IoT sensors. The thermoelectric technology, which is one of the energy harvesting technologies, is a technology that can convert waste heat into electric energy. Although it has several advantages such as small, quiet, and maintenance-free compared with large generations such as a turbine, it has not yet become widely popular. However, the latest research is progressing with a focus on various applications. Here, we introduce research on the anomalous Nernst effect, which is one of the magneto-thermoelectric power generation effects that has attracted attention in recent years as a candidate in the thermoelectric technology. In particular, since the anomalous Nernst effect is a phenomenon that mainly occurs in thin films, it is also expected to be applied to heat flux sensors, which is an application different from thermoelectric power generation. In this chapter, we introduce an overview of the basic research on the anomalous Nernst effect and research that anticipates its application to heat flux sensors.