Vital signs (including breath) monitoring is a key tool in healthcare. Current monitors need invasive electronic sensors attached to user’s body, which is inconvenient and uncomfortable. We demonstrate photonic smart breath monitoring system based on two types of phase-sensitive optical fiber interferometers: traditional fiber Mach-Zehnder interferometer (MZI) and miniaturized fiber modal interferometer (MMI). Users simply lie/sleep on a sensor mat embedded with optical fiber sensor.  Breath will introduce slight strain changes on the mat and affect the light propagating within the fiber.  Breathing waveforms can be achieved by analyzing the output light with signal processing.  The system can collect user’s signals continuously and remotely to provide big data for health analysis. Our technique is non-invasive, highly sensitive, and immune to electromagnetic interference. The author would like to thank the support of HKPU 1-ZVHA.