Starch retrogradation is a complex process, affected by several factors including storage temperature and the presence of non-starch components (such as polysaccharide). In this study, the effects of the endogenous yam non-starch polysaccharide (YNSP) with different concentrations on the yam starch (YS) retrogradation behavior were investigated by asymmetrical flow field-flow fractionation (AF4), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Furthermore, the effects of isothermal and temperature-cycled storage on the retrogradation of YNSP + YS blend were systematically studied. An effect mechanism of the endogenous YNSP on the YS retrogradation during temperature-cycled storage was proposed. The results revealed that 4/-20 °C temperature-cycled storage facilitated YS retrogradation, owing to the formation of starch-rich regions during frozen storage. The mechanical squeezing force caused by the size growth of ice crystal during long-term frozen storage encouraged starch molecules to constantly rearrange, promoting YS retrogradation. Moreover, the YNSP can not only interact with amylose and amylopectin molecules to form aggregates that could promote YS short-term retrogradation, but also compete with amylopectin for water molecules, which might enhance the syneresis process during repeated freeze-chill storage, thereby facilitating YS retrogradation. The results suggested that a combination of AF4, FTIR, and XRD is a powerful method not only for monitoring the interaction between YNSP and YS, but also for investigating the effects of YNSP content and temperature on YS retrogradation. The present study might offer a theoretical foundation and guidance for the application of YNSP to starchy products.Copyright © 2025 Elsevier B.V. All rights reserved.