Route 138 is a numbered State Highway running 48.3 miles (77.7 km) in Rhode Island.

Before the opening of the Jamestown section of the Route 138 Expressway in 1994, Route 138 came off the Jamestown Bridge and used Eldred Avenue (which has now been partially cut off by the Expressway) and East Shore Road to the Newport Pell Bridge.

As of 2005, there is still a Route 138 reassurance marker northbound on East Shore Road just north of the Newport Pell Bridge.

There are two abandoned temporary ramps at the west end of the Jamestown Bridge used by through traffic in the early 1990s.

Route 138A is a numbered state highway running 4.6 miles (7.4 km) through Newport and Middletown, Rhode Island.