The asphaltene was extracted from asphalt cement with penetration grade 60, which is extracted from crude Libya petroleum. The asphalt cement was taken from Tupra Refinery in Izmit-Turkey. The asphalt cement was dissolved in 10 times excess volume of benzene, precipitated in a further 10 times excess volume of petroleum ether with a boiling range of 40-60 degrees C (i.e., 1 part asphalt cement, 10 parts benzene, and 100 parts petroleum ether). The resultant precipitate was collected by filtration and dried. The asphaltene so obtained was dark brown semi-solids. The percentage of asphaltene in the asphalt cement was 30% by weight. Fe4.3Co68.2Si12.5B15 amorphous microwires, with a diameter of 120 m and 12 cm long, were coated with these paramagnetic asphaltene molecules. The giant magneto-impedance effect was experimentally measured on uncoated and asphaltene coated Co-rich amorphous wires. In the asphaltene coated sample, a very high value of the giant magneto-impedance effect ratio up to 42% was achieved at 4.0 MHz. As far as is known, such a giant magneto-impedance enhancement is reported for the first time by an asphaltene coating process.