The novel concept of utilizing a random fiber laser (RFL) to extend the sensing distance of fiber-optic sensing systems is proposed for the first time to our knowledge. In this paper, two schemes based on the RFL with a fiber Bragg grating (FBG) are experimentally demonstrated to verify the concept. The first one is a 100km FBG temperature sensing system, in which a 100km RFL provides an effective way to enhance the sensing signal of the FBG sensor due to its strong lasing radiation across the 100km fiber span. It is the first time to find that the RFL without the FBG is a temperatureinsensitive distributed lasing cavity, which offers stable long-distance transmission for the sensing signal. The second one is a 100km Brilloiun optical time domain analyzer (BOTDA), in which the generated random lasing is used as a fully distributed Raman pump and hence stable Raman amplification can be obtained to enhance the Brilloiun sensing signal. In principle, such a novel concept can be adopted for any type of distributed fiber-optic sensors as the RFL can be used as a stable distributed Raman pump for sensing signal amplification along the whole length of the fiber.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.