The development of oil-resistant materials to eliminate spilled viscous crude oil remains a challenge. Herein, a self-cleaning (anticrude oil-fouling) coating composed of hydrated manganese hydrogen phosphate (MnHPO₄·3H₂O, MHP) is reported. The anticrude oil-fouling property is well correlated with MHP having abundant surface hydrogen phosphate groups. The coating exhibits exceptional binding affinity for water even when fouled by crude oil. Due to the antioil-fouling properties of the MHP coating, copper mesh coated with MHP can separate highly viscous crude oil/water mixtures and crude oil-in-water emulsions before being prewetted with water and can remove floating crude oil from oily wastewater without being prewetted with water, which brings promising for practical applications in spilled crude oil remediation.