An optical evanescent wave coupling te mperature and humidity sensor based on polyvinyl alcohol-aluminum film is propo sed,including a humidity measurement sensor and a temperature compensation sensor.In the single mode fiber fused taper area,the humidity measurement sensor is fabricated after being coated with the polyvinyl alcohol humidity sensitive material film.The temperature compensa tion sensor is fabricated by depositing the aluminum film on the humidity measurement sensor surface.In expe riment,an amplified spontaneous emission (ASE) light source is used for detecting signals and an optical power meter is designed to measure the output of sensor.The humidity measurement sensor is used to detect humidity only,while the temperature compens ation sensor only reflects the variation of environmental temperature.These two sensors work at the same time and the latter is used to compensate the temperature variation in the former.The experimental results sho w that when the taper length is 14.04mm and the polyvinyl alcohol coating thickness is 2.2μm,the humidity se nsitivity is 0.1541dBm/%,the temperature sensitivity is 0.0193dBm/℃,and the humidity mea surement range can achieve 50%~98%.When the aluminum film thickness is 168.63nm,the temperature c ompensation sensor sensitivity is 0.0191dBm/℃.So the developed device can realize the temperature compensation for humidi ty measurement sensor.