Peter J. Somers (April 12, 1850 – February 15, 1924) was an Irish-American mayor of Milwaukee, Wisconsin and member of the United States House of Representatives.

Somers was born in Menomonee Falls, Wisconsin on April 12, 1850.

He served as mayor of Milwaukee from December 6, 1890, to June 5, 1893, when he resigned, having won an election to fill a vacancy in the United States House of Representatives caused by the resignation of John L. Mitchell who was elected to the U.S. Senate.

Somers took over as the representative of Wisconsin's 4th congressional district in the 53rd United States Congress.

He continued practicing law in Milwaukee until 1905, when he moved to Reno, Nevada.