The effect of electron induced reactive processing (EIReP) on the properties of biodegradable polylactide/masticated polycaprolactone (PLA/PCL) blends was firstly investigated without introducing any chemical additives. Subsequently, the melt spinnability of EIReP modified PLA/PCL blends was explored by a piston spinning. The EIReP modified PLA/PCL blends showed improved melt strength and elastic behavior. This is due to the formation of long chain branches and the enhanced chain entanglements. The crystallinity of PLA phase increased from 2.4% to 35.7% as the applied dose increased from 0 to 50 kGy. The PLA/PCL blends treated with 12.5 kGy demonstrated 2.4-fold of impact toughness than that of neat PLA, suggesting a superior interfacial adhesion and chain interactions between two phases. The crystallinity of the PLA/PCL fibers decreased from 33.3% to 17.8% as the applied dose increased from 12.5 kGy to 50 kGy. It is resulted from the hindered chain mobility of branched/grafted structures during fiber formation. The fracture strain of the fibers using a non-irradiated blend was 232.9% which increased to 311.5% for the 50 kGy irradiated blends. However, the fibers spun from irradiated blends demonstrated similar initial modulus but reduced tenacity compared to fibers spun from non-irradiated blend material.