Asphaltene, the cheapest fraction of petroleum, was modified into a novel additive in order to facilitate a deasphalting process, such as paraffinic froth treatment. Asphaltene powder was oxidized by ozone, which is more powerful and less harmful to the environment than other oxidants. The ozonized asphaltene was characterized, and the reaction kinetics of ozonation was interpreted by the shrinking core model. Ozonized asphaltene was added to a water/n-pentane/bitumen emulsion to enhance the precipitation of asphaltene. Control of the properties of the precipitate was allowed by adjusting the ozonation degree and dosage of ozonized asphaltene. The removal of asphaltene was enhanced from 40% to a maximum of 70% by adding ozonized asphaltene under the same conditions. The boiling point distribution of deasphaltened oil indicates that a large amount of residue was removed using ozonized asphaltene. The dispersion behavior was checked by measuring the aggregate size in toluene and alkane solution. It was confirmed that asphaltene and ozonized asphaltene can interact with each other with high affinity.