Lattimer is a village and census-designated place (CDP) in Hazle Township, Luzerne County, Pennsylvania, United States. The population was 554 at the 2010 census.
The Lattimer massacre took place in the village on September 10, 1897; it resulted in the deaths of at least 19 unarmed striking immigrant anthracite coal miners. The miners, mostly of Polish, Slovak, Lithuanian, and German ethnicity, were shot and killed by a Luzerne County sheriff's posse. Scores more were wounded. The massacre was a turning point in the history of the United Mine Workers (UMW).
Lattimer is located at .
According to the United States Census Bureau, the CDP has a total area of , all land. It is located directly northeast of the CDP of Harleigh and lies northeast of the city of Hazleton. Lattimer uses the Hazleton zip code of 18234.