Well-defined chlorinated polyvinylchloride (CPVC) nanofiber mats were fabricated by electrospinning, and then chemically modified with 1,3-propanediamine (CPVC–NH) and glutaraldehyde (CPVC–NOH) to immobilize palladium active species. The chemical modification could significantly improve the tensile strengths of the CPVC nanofiber mats. Adsorption of Pd(II) ions showed that the treatment of fiber mats with glutaraldehyde decreases it schelating ability. Transmission electron microscopy and X-ray diffraction analysis indicated that palladium species were dispersed more homogeneously on the CPVC–NH fibers than on the CPVC–NOH fibers. Results of Mizoroki–Heck reaction showed that the catalytic activity of Pd catalyst supported on CPVC–NOH fibers was superior to that of the Pd catalyst supported on CPVC–NH fibers. Thus, chemical modification of supporting materials with suitable chelating groups is an efficient way to control the catalytic performance of supported Pd catalysts.