Solid filler-reinforced epoxy coatings face two inherent challenges: achieving durable ultra-low friction (μ < 0.05) and preventing interfacial degradation at highly reactive resin/filler interfaces. Harnessing the intrinsic hydrophobicity, defect-compensation capability, and boundary lubrication potential of oil-phase components, this study develops a liquid-phase reinforcement strategy to address the interfacial challenges. Here, oily graphene oxide (TG) microdroplets (T-G) were uniformly dispersed in epoxy resin (EP) via a micellar loading-desorption method, yielding an oil-solid biphasic coating (T-G/EP). The system was further enhanced through micro-arc oxidation (MAO) interlayer integration, establishing a synergistic protective architecture (T-G/EP-on-MAO). T-G/EP-on-MAO exhibited a 92.13 % reduction in friction coefficient (from 0.623 to 0.049) and a 59.52 % decrease in wear rate (from 16.947 × 10 −5 to 6.860 × 10 −5 mm 3/N·m) compared to EP. This enhancement originates from the in situ formation of an oil-based lubricant film enhanced by TG at sliding interfaces. After four weeks of electrochemical testing, T-G/EP-on-MAO exhibited the highest log(Rc) value (Rc = coating resistance) of 7.42. Molecular dynamics simulations unveiled dual protective mechanisms: (i) Oil microdroplets suppress free volume through enhanced molecular packing, concurrently reducing water diffusion coefficients; (ii) Water infiltration preferentially induces intermolecular hydrogen bonding over interactions with highly reactive atoms at TG/resin interfaces, thereby shielding the filler/resin interfacial fragility and restricting water mobility.