The invention relates to a hydraulic oil composition. The hydraulic oil composition contains a screening phenolic compound, an extreme-pressure antiwear additive, a metal deactivator, an antirusting agent, an ashless friction modifier, an anti-emulsifier and a major volume of lubricating oil base oil; and the structure of the screening phenolic compound is represented by a formula (I) shown in the description, wherein all groups in the formula (I) are as defined in the description. The hydraulic oil composition disclosed by the invention can meet the increasingly severe requirements of current higher-specification products on oxidation resistance and further display excellent cleaning and dispersion properties, wear resistance and rust resistance.