西雅图市中心公交隧道（英语：Downtown Seattle Transit Tunnel）是美国华盛顿州西雅图市中心地底的一条公共运输隧道，全长1.3英里（2.1公里），北起第九大道（9th Avenue）和派克街（Pike Street），南至第五大道南（5th Avenue S.）和杰克逊街南（S. Jackson Street）。隧道开通时只供金县大都会运输局的巴士行驶，是世界上第一条投入营运的全封闭地下快速公交系统（BRT）；自2009年起隧道亦供海湾运输署旗下的中央线轻轨（Central Link）行驶。

The Downtown Seattle Transit Tunnel (DSTT), also referred to as the Metro Bus Tunnel, is a 1.3-mile-long (2.1 km) pair of tunnels for public transit that run north–south under 3rd Avenue through Downtown Seattle, Washington from 9th Avenue and Pike Street to 5th Avenue South and South Jackson Street. The double-track tunnel and its stations, with the exception of Convention Place, constitute parts of the Central Link light rail line, with continues north to University of Washington station and south through the Rainier Valley to Seattle–Tacoma International Airport as part of Sound Transit's Link Light Rail network. All five of its stations are also served by buses from King County Metro and Sound Transit Express that leave the tunnel north via Interstate 5, south via the SODO Busway, or east via Interstate 90. The DSTT is the busiest section of the Link Light Rail network, with an average of over 10,000 weekday boardings. It is owned by King County Metro and shared with Sound Transit, having signed a joint-operating agreement after ownership was transferred back to King County in 2002. The Downtown Seattle Transit Tunnel is one of two rail-bus tunnels in the United States, alongside the Mount Washington Transit Tunnel in Pittsburgh, Pennsylvania. However, the DSTT is the only rail-bus tunnel in the United States with stations, as the Mount Washington Transit Tunnel lacks stations.