The disclosed oil purification apparatus comprises: a housing having a purification space formed therein; an inlet formed at one side of the housing and connected to the purification space, into which oil containing at least one of moisture and impurities is introduced; a first outlet formed at an upper side of the housing, through which oil purified in the purification space is discharged; a second outlet formed at a lower side of the housing, through which at least one of the moisture and impurities separated from the oil is discharged; and a filter unit disposed between the inlet and the first outlet in the purification space to remove at least one of the moisture and impurities contained in the oil, wherein the introduced oil passes through the filter unit and is discharged to the first outlet.