Japan Airlines Domestic

Japan Airlines Domestic
日本航空国内線
*Nihonkōkū kokunaisen*
Founded	May 15, 1971; (amalgamation; as Toa Domestic Airlines)
Commenced operations	April 1, 1988; (as Japan Air System); April 1, 2004; (as Japan Airlines Domestic);
Ceased operations	October 1, 2006; (merged into Japan Airlines)
Hubs	Osaka–Itami; Tokyo–Haneda;
Secondary hubs	Fukuoka; Kagoshima; Sapporo–Chitose;
Focus cities	Osaka–Kansai; Tokyo–Narita;
Frequent-flyer program	JAL Mileage Bank
Subsidiaries	Harlequin Air (1997–2005); Hokkaido Air System (1997–2006); Japan Air Commuter (1983–2006);
Fleet size	85
Destinations	46
Parent company	JAL Group
Headquarters	Ōta, Tokyo, Japan
Website	www.jas.co.jp

Japan Air System Co., Ltd. (JAS) (日本エアシステム, Nihon Ea Shisutemu), also known as Japan Airlines Domestic since 2004, was the smallest of the big three Japanese airlines. In contrast to the other two, JAL and ANA, JAS' international route network was very small, but its domestic network incorporated many smaller airports that were not served by the two larger airlines. As an independent company, it was last headquartered in the JAS M1 Building at Haneda Airport in Ōta, Tokyo. It has since merged with Japan Airlines.

JAS was famous for its variety of aircraft liveries; Amy Chavez of The Japan Times described the rainbow liveries as "abstract." Many of its color schemes in the 1990s were designed by film director Akira Kurosawa.

The airline's slogan was "Good Speed Always".