The present disclosure provides isolated monoclonal anti-CD3epsilon antibodies or antigen-binding fragments thereof comprising one or more heavy chain CDR sequences selected from the group consisting of: SEQ ID NOs: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, and 47, and/or one or more kappa light chain CDR sequences selected from the group consisting of: SEQ ID NOs: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46 and 48, isolated polynucleotides encoding the same, pharmaceutical compositions comprising the same, and the use thereof.