Boruch Ber Leibowitz (Yiddish: ברוך בער לייבאוויץ Hebrew: רב ברוך דוב ליבוביץ, romanized: Boruch Dov Libovitz; 1862 – November 17, 1939, known as Reb Boruch Ber, was a rabbi famed for his Talmudic lectures, particularly in that they were rooted styled in the method of his teacher Chaim Soloveitchik. He is known for leading Yeshivas Knesses Beis Yitzchak in Slabodka and Kaminetz.