Jacob Joseph (Hebrew: יעקב יוסף; 1840 – July 28, 1902) served as chief rabbi of New York City's Association of American Orthodox Hebrew Congregations, a federation of Eastern European Jewish synagogues, from 1888 until his death in 1902. Born in Krozhe, a province of Kovno, he studied in the Nevyozer Kloiz under Rabbi Yisrael Salanter and in the Volozhin yeshiva under the Netziv. In Volozhin, he was known as "Rav Yaakov Charif" (Rabbi Jacob Sharp) because of his sharp mind.

He became successively rabbi of Vilon in 1868, Yurburg in 1870, and later in Zhagory. His fame as a preacher spread, so that in 1883 the community of Vilna selected him as its maggid.

The Rabbi Jacob Joseph School, also known as RJJ, is named after him and a playground is named after and honors the memory of a great-grandson of Rabbi Jacob Joseph who carried his name.

Some in the Jewish community of New York wanted to be united under a common religious authority, and although the Reform and liberal factions ridiculed the idea, the mainly Russian Orthodox Ashkenazi community sent a circular offering the post throughout Eastern Europe.

Rabbi Jacob Joseph was among those offered the prestigious position. He hesitated in coming to America, aware that there were fewer religious Jews. Nevertheless, in 1888 he accepted the challenge in order to support his family, and also because he faced severe debt in Russia. The Association of American Orthodox Hebrew Congregations—comprising 18 congregations and headed by Beth Hamedrash Hagadol—was pleased when he accepted the position.

They attempted to create one central rabbinic authority in America to maintain order in the field of Kashrus and expand Jewish education programs. Their idea ultimately failed. Although Joseph certainly possessed the credentials needed, he was confronted with many problems and his tenure was marked by the divisiveness of New York Jewry. His right to exercise authority over New York's Jewish communities was questioned because, in addition to his Orthodox supporters of Eastern European heritage, the community also included Ashkenazi Orthodox Jews from other areas of Europe, Orthodox Jews who had been in America for generations and did not welcome him as a source of authority, Ashkenazi Jews of the Reform denomination, Sephardic Jews, Mizrahi Jews, anti-religious Jews, and Jewish Communists.

Most of the disputation arose in regard to the kosher slaughterhouses of the city. To support the rabbi, a small charge was made for his certification of kosher meat, which was paid by the customer. Some customers felt that the imposition of this fee for kosher certification was similar to the taxes that antisemitic governments had imposed on kosher meat in Europe and Russia. Some felt that it drove the price of meat higher for no good reason. Others wanted a return to the days when they could simply trust their own kosher butchers, without the approval of a foreign rabbi, who did not even speak English. These disputes became personal when culturally Jewish but anti-religious Yiddish newspapers opposed to the concept of a centralized Orthodox rabbinical authority printed unflattering rumours about the chief rabbi's personal life. Eventually, after six years, the Association stopped paying the rabbi's salary. The butchers then paid him until 1895. This did not stop the conflict, however, for when the butchers paid his fees, charges were made that the rabbi might certify non-kosher meat simply for the money.

Although Joseph fought a losing battle in the kosher meat and poultry industry, he managed to achieve some notable accomplishments, including the hiring of qualified shochtim, introducing irremovable seals ("plumba") to identify kosher birds, and setting up Mashgichim to oversee slaughter houses. He also took an active role in establishing the Etz Chaim Yeshiva—the first yeshiva on the Lower East Side, which was founded in 1886. (It was the forerunner of the Rabbi Isaac Elchanan Theological Seminary.)