Shmuel Aaron Mermelstein was born in Montreal, Canada on April 4 1961 to Emil (mother's name unknown).
He completed his Yeshiva high school studies in Montreal and graduated from Yeshiva University.
He came to Israel in the late 1970s and began studying in the Kerem B'Yavneh yeshiva. On Erev Shabbat, May 2, 1980, as a group of worshippers made their way from the Tomb of the Patriarchs (Maarat Hamachpela) to Beit Hadassah, they were ambushed by terrorists. Sixteen people were wounded and five were killed, including Shmuel.