The 1934 West Coast Waterfront Strike (also known as the 1934 West Coast Longshoremen's Strike, as well as a number of variations on these names) lasted eighty-three days, and began on May 9, 1934 when longshoremen in every US West Coast port walked out. Organized by the International Longshore and Warehouse Union (ILWU), the strike peaked with the death of two workers on "Bloody Thursday" and the San Francisco General Strike which stopped all work in the major port city for four days and led ultimately to the settlement of the West Coast Longshoremen's Strike.

The result of the strike was the unionization of all of the West Coast ports of the United States. The San Francisco General Strike of 1934, along with the Toledo Auto-Lite Strike of 1934 led by the American Workers Party and the Minneapolis Teamsters Strike of 1934 led by the Communist League of America, were catalysts for the rise of industrial unionism in the 1930s, much of which was organized through the Congress of Industrial Organizations.