Abstract: Aiming at the industry bottleneck of high oil content and high calorie of fried instant noodles, as well as the research gap on the application of functional oligosaccharides in fried instant noodles, this study aimed to investigate the effects of different addition levels of isomaltooligosaccharides 90 (IMO-90) on the processing characteristics and final product quality of fried instant noodles. In this experiment, fried instant noodles were prepared by replacing wheat flour with IMO-90 at the ratios of 5%, 10% and 15%, respectively. The rheological properties and tensile properties of dough were analyzed by dynamic rheological test and uniaxial tensile test, the microstructure of dough was observed by scanning electron microscope (SEM), the water distribution state of dough was analyzed by low-field nuclear magnetic resonance (LF-NMR), and the cooking properties, texture properties, color, oil content and sensory quality of the final instant noodles were systematically determined. The results showed that the addition of IMO-90 reduced the dough strength and deformation resistance, improved the dough extensibility, and the effect showed an increasing trend with the increase of addition level. IMO-90 destroyed the continuity of gluten network, promoted the formation of more porous structure in dough system, changed the water distribution of dough, and converted part of bound water to loosely bound water. The addition of IMO-90 did not significantly reduce the cooking quality of fried instant noodles, and shortened the rehydration time of the product, with the water absorption of the final product reaching the peak at 10% addition level. IMO-90 significantly reduced the oil content of the product, which decreased to 12.4% at 15% addition level, and improved the color and flavor of the product by promoting the Maillard reaction. The comprehensive quality evaluation showed that the fried instant noodles had the best comprehensive quality when IMO-90 replaced 10% of wheat flour. The results of this study provide a systematic theoretical basis for the application of oligosaccharides in the development of fried instant noodles with low oil content and low calorie.