Liquid chromatography-mass spectrometry (LC-MS) is a highly sophisticated analytical technique that has become indispensable for sample analysis across various scientific domains. In recent years, LC-MS has emerged as a cornerstone technology in comparative replicate sample analysis, particularly in the fields of proteomics, lipidomics and metabolomics. This review provides a comprehensive and in-depth exploration of LC-MS applications in biological, and applied sciences from the key aspects include (1) a historical perspective on LC-MS development and advancements; (2) its critical role in forensic investigations and environmental science; (3) its applications in food safety, quality control and pharmaceutical analysis and (4) its significance in the examination of pharmaceuticals and biological specimens. By presenting a broad and integrated understanding of LC-MS, this review underscores its transformative impact on life sciences and its expanding role in scientific research and innovation.