An anti leakage device of lubrication oil for a fan includes a hub seat, a sleeve and a hub. The sleeve is provided on the hub seat and has a bearing therein to form an oil storage part for receiving lubrication oil. The hub is provided on the hub seat and has an annular recess at the inside thereof for being inserted with the sleeve. Hence, leakage from the oil storage part can be avoided by way of provision of the annular recess.