Abstract: A new type of asphalt dispersant was prepared by using polyisobutylene succinimide, imidazole，and salicylaldehyde as materials and characterized by FT-IR. The effects of molar ratio of the material，reaction time and temperature on the scale inhibition performance of the product were investigated；the weight loss analysis was used to test the corrosion inhibition performance of product; and the effect of the ratio of scale inhibitor components on the asphaltene inhibition was discussed. The results show that the best synthetic conditions for asphalt dispersant are: mole ratio of 2:2:1 for polyisobutylene succinimide: imidazole: salicylaldehyd, and reaction time of 5 h at 140 ℃. IR spectrum shows that the desired product is synthesized；No thermal weight loss in 200—380 ℃ indicates the good thermal stability of the product. When 150 μg/g product was added, the asphaltene inhibition rate is up to 79.0%，and the corrosion-inhibiting rate is up to 84.6%.

Key words: asphalt dispersant, scale inhibitor, catalytic slurry, scale inhibition performance