Isidore Nagler (February 25, 1895 – September 21, 1959) was a Galician-born Jewish American labor leader who served as vice president of the International Ladies Garment Workers Union from 1929 until his death in 1959.

[1] Nagler emigrated to the United States in 1909, and worked in the clothing industry, joining Local 10 of the International Ladies Garment Workers' Union (ILGWU) in 1911.

He soon rose to become business manager of the local, also serving on the New York Cloak Joint Board, and later becoming a vice president of the ILGWU.

In 1937 he ran for Bronx Borough President on the ALP ticket, coming in second place with 39% of the vote.

[4] In 1958, he served as labor adviser to the United States delegation to the International Labour Organization conference.