The San Bernardino road tunnel is a road tunnel in the canton of Graubünden in south-eastern Switzerland. It runs under the San Bernardino Pass between the town of San Bernardino and the town of Hinterrhein, and forms part of the A13 motorway and the European route E43. The tunnel was completed in 1967 and is 6,596 metres (21,640 ft) long. Since the opening of the tunnel, the Val Mesolcina, one of the Italian-speaking southern valleys of Graubünden, is now connected all-year round with the rest of the canton.

The San Bernardino Tunnel is part of the A13 as a single-carriageway freeway and therefore passes through one bore without a central physical structure. As there is only one lane per direction, overtaking (passing other vehicles) inside the tunnel is not permitted.