A new method of dry mixing and weighing was presented to evaluate the adhesion between Buton rock asphalt and coarse aggregate according to size variation, with a quantitative index, adhesion coefficient δ, on which the influence of pre heating temperature and lithological characters of coarse aggregates had been also analyzed. Besides, the effectiveness of the method mentioned above to evaluate the adhesion between BRA and coarse aggregate was affirmed by analysing the adhesion work of different BRA coarse aggregate systems based on surface energy theory. The results show that both pre heating temperature and coarse aggregate types have a significant impact on the adhesion, and the recommended pre heating temperature for BRA is 9096℃.