Moses Mielziner (August 12, 1828 in Schubin, Grand Duchy of Posen, Prussia - February 18, 1903 in Cincinnati) was an American Reform rabbi and author.
The Orthodox reaction introduced by the "Landrabbiner" Baruch Isaac Lipschütz in 1853 forced Mielziner, much to the regret of his congregation, to resign his position.
Apart from several sermons which he published, the first of which was delivered in Waren, 1854, he wrote Die Verhältnisse der Sklaven bei den Hebräern, Copenhagen, 1859, this being the thesis for which he received the degree of Ph.D. from the University of Giessen.
As a result of his college lectures he published: Mielziner edited a Danish almanac for the year 5622 = 1862–63, and A Selection from the Psalms for School and Family, Cincinnati, 1890.
Of the seven children who survived him, Leo Mielziner was an artist in Paris and Jacob was a rabbi in Helena, Montana.