In order to measure and monitor the temperature of various nanoscale substances or biological structures such as subcellular, especially to monitor local temperature changes such as living cells and organelles in vivo, it is of great significance to develop available nanoscale temperature measurement techniques for single cells. In recent years, nanothermometers have shown excellent performance with higher precision and higher sensitivity than earlier thermometers, providing a variety of multifunctional, high-durability nano-temperature sensors that make it possible to perform at higher time and space. Higher resolution enables monitoring of temperature changes in intracellular organelles during various physiological activities and metabolisms. With rapidly development, recent studies have shown that in some directions, nanothermometers still have some unavoidable limitations to overcome. Here, we present various design strategies and device developments used to construct nanothermometers in recent years, as well as their application prospects. As a new direction in the interdisciplinary field, possible opportunities and challenges are analyzed and discussed, and improvements to this cross-cutting field are proposed.