The Asatō Line (阿佐東線, Asatō-sen, lit. 'Asa East Line') is a Japanese railway line connecting Kaifu Station, Kaiyō and Kannoura Station, Tōyō. Together with JR Shikoku's Mugi Line, it has the official nickname Awa Muroto Seaside Line (阿波室戸シーサイドライン, Awa Muroto Shīsaido Rain). This is the only railway line operated by Asa Coast Railway Company (阿佐海岸鉄道株式会社, Asa Kaigan Tetsudō kabushiki-gaisha). The company's name is abbreviated to the portmanteau Asatetsu (阿佐鉄). Since the line goes through a relatively sparsely populated area, it is under severe business stress, to the point where closure of the line has been proposed.

The railway company commenced operating road–rail vehicles, known as DMV (dual-mode vehicle) in Japan, on the Asato Line from 25 December 2021.

The vehicles used are 3 extensively modified Toyota Coaster minibuses, claimed to be the first in the world, which enable through service to locations without rail infrastructure. The vehicles are classed as DMV93 type.

In preparation, the rail line was disconnected from the Mugi Line in summer 2019.