The Full Form of MLS is Medical Laboratory Science.

A medical laboratory scientist (MLS), also traditionally referred to as a clinical laboratory scientist (CLS), or medical technologist (MT), is a healthcare professional who performs chemical, hematological, immunologic, histopathological, cytopathological, microscopic, and bacteriological diagnostic analyses on body fluids such as blood, urine, sputum, stool, cerebrospinal fluid (CSF), peritoneal fluid, pericardial fluid, and synovial fluid, as well as other specimens. Medical laboratory scientists work in clinical laboratories at hospitals, reference labs, biotechnology labs and non-clinical industrial labs. Those that work in non clinical industrial labs are often referred to as biomedical laboratory technologist (BLT) in parts of the world.