| MTSO | Mobile Telephone Switching Office | 移动电话交换局 |
| MTSO | Medical Transcription Service Organization | 医疗转录服务组织 |
| MTSO | Methodist Theological School in Ohio | 俄亥俄州卫理公会神学学校 |
| MTSO | Mobile Telecommunications Switching Office | 移动电信交换局 |
| MTSO | Meteorological Telecommunications System Offenbach | 奥芬巴赫气象电信系统 |