Ultra-miniature surface-mountable Fabry-Perot pressure sensor is constructed on an optical fiber which utilizes a 45° angled fiber tip covered with a reflective layer which steers the optical axis of the fiber by 90°. The Fabry-Perot cavity is formed on the sidewall of the fiber and a polymer-metal composite diaphragm is formed on the top of the Fabry-Perot cavity to operate as a pressure transducer. The sensor exhibits a sufficient linearity over the broad pressure range with a high sensitivity. The sensitivity of the sensor may be tuned by controlling the thickness of the diaphragm. The sensor may be used in a wide range of applications, including reliable in vivo low invasive pressure measurements of biological fluids, single sensor systems, as well as integral spatial-division-multiplexing sensor networks. Methods of batch production of uniform device-to-device Fabry-Perot pressure sensors of co-axial and cross-axial configurations are presented.