Reinhold Sadler (January 10, 1848 – January 30, 1906) was an American politician. He was the ninth Governor of Nevada. He was a member of the Silver Party.
Sadler was born on January 10, 1848 in Czarnikau, Posen Province, Prussia. His education was limited to the common schools of his native country. He immigrated to America first moving to Virginia City, and later Eureka. He married Louise Zadow in Hamilton, Nevada on May 26, 1874, and the couple had six children, Wihlemina, William Arthur, Bertha, Edgar, Alfred and Clarence.
Sadler settled in Eureka, Nevada and worked as a miner, a miller, and a merchant. He was elected treasurer of Eureka County in 1880.
After two unsuccessful campaigns for state offices, he was elected the tenth Lieutenant Governor in 1895. After the death of Governor John E. Jones, Sadler became Acting Governor, making him only the third foreign-born governor of Nevada,; he was elected Governor in his own right in 1898. During his tenure, the Farmer's Institute was launched and the State Board of Assessors was established.