Samuel Shaw (Ulysses) Arentz (January 8, 1879 – June 17, 1934) was a United States representative from Nevada.

He was engaged as surveyor, assessor, miner, and timberman in Bear Gulch and Butte, of Montana; the Bingham Canyon and Stockton, Utah; and the Lake Superior copper country, mining engineer and superintendent of mines in Idaho, Utah, Arizona, and Nevada.

He was not renominated, and was an unsuccessful candidate in the 1922 Republican primary election for United States Senator.

He was a delegate to the Republican National Conventions in 1928 and 1932, and again engaged as a rancher near Simpson.

Arentz died in Reno, Nevada, where he had gone to receive medical treatment, on June 17, 1934.