A high-capacity oil sorbent is fabricated by electrospinning a polystyrene and polyacrylonitrile blend. The influences of several processing parameters including the spinning solution concentration, environmental temperature, applied voltage, relative humidity, and inner diameter of the metal needle on the morphology and oil sorption capacity are investigated. All the parameters are found to have an effect on the morphology and sorption capacity; furthermore, the relative humidity plays an important role in determining the fiber surface roughness. The highest sorption capacity is obtained under the following conditions: the spinning solution concentration is 18%, the environmental temperature is 30?, the applied voltage is 25kV, the relative humidity is 40%, and the nozzle inner diameter of metal needle is 0.6mm. This produces a fibrous sorbent with uniform morphology, a thinner diameter, and the highest sorption capacity. The maximum sorption capacities of the polystyrene/polyacrylonitrile sorbent for pump oil, peanut oil, diesel, and gasoline are 194.85, 131.7, 66.75, and 43.38g/g, respectively. Polystyrene/polyacrylonitrile fiber is compared with polystyrene fiber through mechanical tests. The sorption kinetic data for the four oils could be well described by the pseudo-second order rate equation. The sorption equilibrium time for pump oil, peanut oil, diesel, and gasoline was 56.27, 16.24, 5.16, and 3.52min, respectively.