Bridge construction along the Alaska Highway was crucial to the success of the road. During the 1942 construction season, temporary timber bridges were constructed by the U.S. Army Engineers and civilian contractors hired by the U.S. Public Roads Administration. Typically, a pontoon bridge was set up first using pontoon boats and timber. These makeshift structures were meant only for transporting equipment until timber bridges could be constructed alongside them. Early in 1942, ice bridges were also used to transport construction equipment and supplies.

During the 1943 construction season, the U.S. Public Roads Administration upgraded the highway from "pioneer road" status and built 133 permanent bridges. Civilian companies were hired to build the bridges. Ninety-nine permanent bridges were completed by October 1943, but wartime steel shortages delayed construction of the remaining bridges until 1944. Construction material of permanent bridges varied: about one half were wooden trestle spans, a few were built of reinforced concrete, and the rest were steel. In some cases, unused bridges in the United States were dismantled and reassembled on new foundations on the Alaska Highway.