Rabbi Yechiel Michel HaLevi Epstein was born on 20 Shevat 5589 (January 24, 1829) in Babruysk, Belarus, to Aharon Yitzchak, a contractor who traveled extensively for his work, and Rashka. According to family tradition, the Epsteins were a branch of the Sephardic Benveniste family.

He originally intended to follow his father into commerce, but Rabbi Eliyahu Goldberg, later av beis din of Babruysk, persuaded him to devote himself fully to Torah; he then studied for two years at the Volozhin yeshiva. He married Michlah, daughter of Rabbi Yaakov Berlin and sister of the Netziv of Volozhin, with whom he remained close all his life. Back in Babruysk he taught in the local yeshiva and sat as a dayan on Rabbi Goldberg's beis din, while his wife ran a fabric store that supported the family. After losing his money, he resolved to enter the rabbinate.

He first served as rabbi of Novozybkov, a largely Chassidic town in Russia, where he published his first work, Ohr LaYesharim, on Rabbeinu Tam's Sefer HaYashar. He then became rabbi of Novardok, a post he held for thirty-four years until his death. He would travel to Saint Petersburg, staying with his brother Binyamin Beinush, to submit his writings to the Russian censor. Firm in his conduct as a rabbi, in halachic rulings he sought a lenient path whenever possible. He ordained many rabbis, among them Rabbi Isser Zalman Meltzer, Rav Kook and Rabbi Yechezkel Abramsky.

Works: Aruch HaShulchan, a vast code covering all four parts of the Shulchan Aruch, tracing each law back to the Talmud and the Rishonim before arriving at the practical ruling, whose title became his name; Aruch HaShulchan HeAtid, on the laws that will apply in the Land of Israel and in the time of the Temple; Ohr LaYesharim; Michal HaMayim on the Jerusalem Talmud; and Leil Shimurim on the Pesach Haggadah.

He was the father of Rabbi Baruch HaLevi Epstein, author of the Torah Temimah; his daughter Batya Miriam became the second wife of the Netziv, and their son was Rabbi Meir Bar-Ilan. He passed away in Novardok on 22 Adar II 5668 (March 25, 1908) and was buried there.