During the Bolshevik revolution Rabbi Isser Zalman Meltzer fled with the Slutsk Yeshiva from Belarus to Lithuania taking along his son in law Rabbi Aharon Kotler. For the next several years Rabbi Yechiel Michel religiously attended the lectures of Rabbi Meltzer and Rabbi Kotler. At the age of seventeen, Rabbi Yechiel Michel transferred to the Mir yeshiva in Poland, where he became a student of the great leader of Mussar Rabbi Yeruchim Levovitz. In Mir, Rabbi Yechiel Michel befriended Rabbi Dovid Povarsky, who later became the dean of Ponevez Yeshiva. At the same time the Mir Yeshiva hosted such illustrious scholars as Rabbi Chaim Shmuelevitz and Rabbi Aryeh Leib Malin. Despite being surrounding by such luminaries in Torah, Rabbi Yechiel Michel was nonetheless thought of as the genius of his yeshiva. At the suggestion of his mentor Rabbi Isser Zalman Meltzer, Rabbi Yechiel Michel Feinstein went to the city of Brisk in Belarus to study under the illustrious Chief Rabbi of Brisk, Rabbi Yitzchok Zev Soloveichik.

Rabbi Yechiel Michel Feinstein was fearful of being conscripted into the army. He travelled to Radin to consult with Rabbi Yisrael Meir Kagan, the Chofetz Chaim, who was astounded at Rabbi Yechiel Michel's broad knowledge of Talmud. He stayed in Grodno for half a year, where he studied under Rabbi Shimon Shkop. He then returned to Brisk to continue his studies under Rabbi Yitzchok Zev Soloveichik. He would return to the Mir Yeshiva for the summer months and for the month of Elul. When World War II broke out, Many Yeshivohs transferred to Vilna. When students of the Mir Yeshiva left for Vilna, Rabbi Yechiel Michel Feinstein went along with them. In Vilna, Rabbi Yechiel Michel was befriended by the great leader of European Jewry, Rabbi Chaim Ozer Grodzensky, who heaped tremendous praise on him.

From Vilna he joined the Mir Yeshiva which travelled to Japan to wait out the war. In 1941, Rabbi Yechiel Michel Feinstein arrived in the United States of America with Rabbi Aharon Kotler. Rabbi Kotler opened a yeshiva in Lakewood, New Jersey and at the same time Rabbi Yechiel Michel was invited to serve as Mashgiach at the Yeshiva Heichal Rabbeinu Chaim Halevi in Boston under Rabbi Joseph Dov Soloveichik. But that same year, Rabbi Yechiel Michel accepted an invitation by his uncle Rabbi Moshe Feinstein to serve at his side as the head of Mesivta Tiferes Yerushalayim which was located in the Lower East Side of Manhattan. Rabbi Yechiel Michel soon gained great fame for his deep Talmudic lectures. The Agudas Harabbanim, under the leadership of Rabbi Eliezer Silver and Rabbi Moshe Feinstein also appointed Rabbi Yechiel Michel a member of the organization, and he played a crucial role in helping save refugees from the Holocaust in Europe.

In 1946, Rabbi Yechiel Michel Feinstein immigrated to Palestine to reunite with his mentor Rabbi Yitzchok Zev Soloveichik of Brisk. He married Rabbi Soloveitchik's daughter Lifsha. Rabbi Isser Zalman Meltzer, his former Rosh Yeshiva at Slutsk, who had also immigrated to Palestine, officiated at the wedding. Rabbi Yechiel Michel moved to Tel Aviv in 1952 to establish a yeshiva, but frequently travelled to Bnei Brak to consult with the Chazon Ish on important issues. In 1973 Rabbi Yechiel Michel moved to Bnei Brak and opened a yeshiva where he gave more than seventeen complex lectures per week.

Rabbi Yechiel Michel Feinstein passed away in 2003. His many wonderful lectures on the Talmud are being prepared for publication. Rabbi Yechiel Michel Feinstein is a signatory on the historic 1979 Kol Koreh (broadside) on behalf of Rabbi Meir Baal Haneis Salant, together with such Torah giants such as Rabbi Yaakov Kamenetsky, Rabbi Yaakov Yisroel Kanievsky The "Steipler", Rabbi Shloma Zalman Auerbach, Rabbi Elazar Simcha Wasserman, Rabbi Dovid Povarsky, Rabbi Moshe Shmuel Shapiro, Rabbi Shmuel Birnbaum, and many, many others. May their memory be a blessing to all.