We propose, fabricate, and demonstrate a compact fiber-tip Fabry-Perot interferometer of microcavity for high-temperature sensing. The microcavity which can be used for temperature or pressure sensing is fabricated by using arc discharge at the end of a multimode fiber, which is processed with chemical etching. Advantages of the sensor based on the fiber-tip Fabry-Perot interferometer are small size, easy fabrication, low cost and may have potential applications in space-limited and high-temperature environment.