The Rock Springs massacre, also known as the Rock Springs Riot, occurs on September 2, 1885, in the present-day United States city of Rock Springs, Wyoming, in Sweetwater County.

The riot, between Chinese immigrant miners and white immigrant miners, is the result of racial tensions and an ongoing labor dispute over the Union Pacific Coal Department's policy of paying Chinese miners lower wages than white miners.

This policy causes the Chinese to be hired over the white miners, which further angers the white miners and contributes to the riot.

Racial tensions are an even bigger factor in the massacre.

When the rioting ends, at least 28 Chinese miners are dead and 15 are injured.

Rioters burn 75 Chinese homes resulting in approximately US$150,000 in property damage ($3.88 million in present-day terms).Tension between whites and Chinese immigrants in the late 19th century American West is particularly high, especially in the decade preceding the violence.

The massacre in Rock Springs is the violent outburst of years of anti-Chinese sentiment in the United States.

The 1882 Chinese Exclusion Act suspends Chinese immigration for ten years, but not before thousands of immigrants have come to the American West.

Most Chinese immigrants to Wyoming Territory take jobs with the railroad at first, but many end up employed in coal mines owned by the Union Pacific Railroad.

As Chinese immigration increases, so does anti-Chinese sentiment from whites.

The Knights of Labor, one of the foremost voices against Chinese immigrant labor, forms a chapter in Rock Springs in 1883, and most rioters are members of this organization.

However, no direct connection is ever established linking the riot to the national Knights of Labor organization.

In the immediate aftermath of the riot, federal troops are deployed in Rock Springs.

They escort the surviving Chinese miners, most of whom had fled to Evanston, Wyoming, back to Rock Springs a week after the riot.

Reaction comes swiftly from the era's publications.

In Rock Springs, the local newspaper endorses the outcome of the riot, while in other Wyoming newspapers, support for the riot is limited to sympathy for the causes of the white miners.

The massacre in Rock Springs touches off a wave of anti-Chinese violence, especially in the Puget Sound area of Washington Territory.