Silicon material is the most promising high energy density anode material because its specific capacity (4200 mA h/g) is more than 10 times higher than that of commercial graphite anode (372 mA h/g). However, the huge volume change of silicon anode materials during charging and discharging, resulting in irreversible capacity loss and low initial coulombic efficiency, makes the practical application of silicon anode limited. In order to reduce the volume change effect, in this research, micron Si and nano-amorphous SiO₂ (Nano-SiO₂) were synthesised by sand milling with anhydrous ethanol as the abrasive agent to form micro-nano Si/SiO₂ composites (SNSO), and nano-Fe₂O₃ was introduced to prepare Fe₂O₃-modified Si/SiO₂ composites (SNSO@Fe₂O₃) by mechanical ball milling. XRD, XPS, SEM and TEM were used to characterise the modified composites and test their electrochemical properties. The results show that SNSO and Fe₂O₃ present a regular spherical core-shell structure with an amorphous layer in the outer shell under the action of high-energy ball milling, and the modified samples exhibit excellent cycling performance, with the reversible specific capacity remaining stable above 986 mA h/g after 100 cycles at a current density of 110 mA/g, which is an enhancement of about 43% compared with that of SNSO. Its stable cycling performance is attributed to the generation of FeSi phase during ball milling and the amorphous layer shell structure formed on the Si surface by the in-situ reaction of amorphous SiO_x and Fe₂O₃, which effectively mitigates the volume expansion of Si.