The first self-immolative polymer (SIP) nanofiber: membrane is demonstrated in this report, in which the immolation can be triggered by external stimulus. Electrospun SIP/polyacrylonitrile (PAN) fibers provide depolymetization that is similar to 25 times quicker and more responsive (i.e., immolation) than that of a cast film in 'the triggering condition. Depolymerization of SIP in the SIP/PAN blended fiber membrane results in the transition of the surface properties from hydrophobic (similar to 110 degrees) to hygroscopic (similar to 0 degrees). Triggered release of encapsulated functional molecules was demonstrated using coaxially electrospun fiber made of a SIP/PAN sheath and polyvinylpyrrolidone/dye core. Coaxial fibers with the SIP/PAN sheath provide minimal release of the encapsulated material in nontriggering solution, while it releases the encapsulated material instantly when the triggering condition is met. Its versatility has been strengthened compared to that of non -SIP coaxial fibers that provide no triggering reaction by external stimulus.