The Pulp Mill Covered Bridge, also called the Paper Mill Covered Bridge, is a wooden covered bridge that crosses Otter Creek between Middlebury and Weybridge, Vermont on Seymour Street. 

The bridge is of Burr arch design. Around 1860, the original Burr arches were removed, and laminated ones were added to King post trusses, changing the bridge type to a King post with Burr arch design. This bridge has many distinctions. It is one of only six remaining double-barreled (two-lane) covered bridges in the country, one of only two in the State of Vermont, and the only one still carrying regular traffic. Built supposedly in 1820, it is also the oldest covered bridge in Vermont, and one of the oldest in the country.

The exact age of the bridge is in question. A sign on the bridge states it was built between 1808 and 1820. Covered Bridge expert Jan Lewandosky has placed the year of construction at approximately 1850 based on his search of Minutes of the Selectboard of the Town of Middlebury, and his voluminous knowledge of covered bridge construction. In 1850 the Town of Middlebury sent a person to Essex, Vermont to examine a recently completed Burr Arch bridge, unfortunately, the design was not copied correctly leading to the design flaws.

The bridge was originally built as a single span but inherent design problems, and heavy use, have driven almost constant improvements. Amongst those improvements was the addition of two piers in the creek effectively dividing the bridge into 3 spans. A non-structural improvement was the addition of a walkway on the outside of the bridge by the Towns of Weybridge and Middlebury, as well as several other rounds of repairs over its' long history.

The Pulp Mill bridge was closed from January 2, 2012, until November 9, 2012, for rehabilitation.

There are just over 100 authentic covered bridges in the U.S. state of Vermont, giving the state the highest number of covered bridges per square mile in the United States. A covered bridge is considered authentic not due to its age but by its construction.

Of the over 500 covered bridges built in Vermont, as of 2019, only 104 remain. 

It was listed on the National Register of Historic Places in 1974.