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In this work, the effect of heat moisture treatment on the physicochemical properties of oak acorn starch has been studied. Heat moisture treatment was performed by microwave (HMT-Mw), hot air oven (HMT-Hao) and autoclave (HMT-Ac) with starch samples conditioned at 25% moisture (p / p). The solubility of the three modified starches increased, with values of 18, 20 and 34% for HMT-Ac, HMT-Hao and HMT-Mw respectively. The swelling power also increased for HMT-Hao and HMT-Mw about 16g/g, but it was lower for HMT-Ac (11g/g) than native starch. The amylose content of the modified starches HMT-Mw and HMT-Hao increased while that of HMT-Ac decreased. HMT modification of acorn starch causes a decrease in its intrinsic viscosity and molecular weight. In the FT-IR analysis, no effect was observed on the molecular composition (functional groups) after physical modification. X-ray diffraction study presents a B-type of acorn native starch which changed to A-type after heat moisture treatment by Mw, Ac and Hao. However, differences were observed in pics intensities and crystallinity was increased by HMT