This work proposes a design, fabrication, and characterization of flexible temperature sensors using temperature-sensitive materials, which are applied using a drop coating method. Temperature-sensitive materials were fabricated by mixing poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) with polyaniline (PEDOT:PSS/PANI). The temperature coefficient of resistance reached −0.803%/°C. Moreover, the detection resolution reached 0.1 °C and had a fast response time of 200 ms. In addition, the sensor can sense spatial temperatures. The sensor has the advantages of low cost, a simple preparation process, and the potential to be used in medical rehabilitation and early disease prevention.