Fiber-optic surface plasmon resonance (SPR) sensing is one of the research focuses in fiber-optic sensing filed. Various structures and merits of fiber-optic SPR sensors are discussed in detail, and influences of material and thickness of the metal film, the length of the coated optical fiber, the combination and the thickness ratio of double-layer metal film on the performance of fiber-optic SPR sensors are analyzed. Research progresses and applications of fiber-optic SPR sensors are summarized, including multi-mode fiber-optic SPR sensors, single-mode fiber-optic SPR sensors, fiber Bragg grating SPR sensors, tilt fiber grating SPR sensors, long-period fiber grating SPR sensors, multi-channel fiber-optic SPR sensors, photonic crystal fiber-optic SPR sensors and nano-metal-particle fiber-optic SPR sensors. Research emphasis and development direction of fiber-optic SPR sensors are given.