Cerebral temperature is one of the key indicators of fever, trauma, and physical activity. It has been reported that the temperature of the healthy brain is up to 2 °C higher than the core body temperature. The main methods to monitor brain temperature include infrared spectroscopy, radiometry, and acoustic thermometry. While these methods are useful, they are not very effective when portability is desired, the temperature needs to be monitored for a longer period, or localized monitoring is required. This paper presents a short review of invasive and non-invasive brain temperature monitoring sensors and tools. We discuss the type of temperature sensors that can be integrated with probes. Furthermore, implantable and bioresorbable sensors are briefly mentioned. Biocompatibility and invasiveness of the sensors in terms of their functional materials, encapsulation, and size are highlighted.