Mišelis-Leiba Šimanovičius (1920–?) was born in Kybartai, in the family of Morduchas Šimanovičius and Bahl Galdė Sacharevičiūtė. In 1937, he graduated from the coeducational school of humanities Tarbut, with instruction in Hebrew. In 1939, he graduated from the Pedagogical Institute. In 1939, he was admitted to the Faculty of Law of Stephen Báthory University. This is because on 15 January 1940 he submitted a request to study in the Semitology Group of the Department of Philology of the Faculty of Humanities of Vilnius University and indicated that his documents were at the Faculty of Law. He was not accepted in the desired study programme and in the autumn of the same year submitted a second application to study at the Department of Physics of the Faculty of Mathematics and Nature of Vilnius University. He was accepted but studied there briefly because on 19 September 1941 he was expelled from the university on the basis of the Order of 17 September 1941 of the Higher Education Department of the Board of Education, under the authority of the National Socialists. No information on the further fate of Mišelis-Leiba Šimanovičius is known. According to the Yad Vashem Holocaust victim database, it can be assumed he was killed during the Holocaust.