Abstract: As environmental factors become more and more important to road alignment design‚the idea of the unifica-tion between the interior and exterior harmoniousness in road alignment design was proposed on the basis of the design principle that road alignment should be in harmony with environment landscape．Furthermore‚some problems to be fully considered to realize the harmoniousness were expounded．These problems involve the horizontal and vertical design of the road alignment‚the horizontal and vertical combination design of the road alignment‚the road corresponding with the landform and the vegetation‚and road virescence．By using the methods of project practice analysis and road alignment scenograph analysis‚some effective ways to solve the above-mentioned problems were clarified‚by which the road will be of more security‚harmoniousness and comfortableness．

Key words: road alignment design, environment landscape, interior harmoniousness, exterior harmoniousness