For years, cancer has been the second cause of death worldwide, preceded by cardiovascular diseases only. The number of research groups focusing on the discovery of new drugs to treat cancer is growing and the aim is to look for more effective compounds that cause less severe side effects and do not suffer from therapeutic resistance. The metal complexes cisplatin and carboplatin are widely used in the chemotherapeutic treatment of various types of cancer, including triple-negative breast cancer (TNBC). Both compounds are essential in modern chemotherapy and continue to be the subject of research to optimize their therapeutic properties and minimize adverse effects. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) allows obtaining both quantitative data and information on the spatial distribution of elements in biological tissues and populations of single cells. In this work, the content of Pt and its distribution in TNBC MDA-MB-231 cells were determined via LA-ICP-MS analysis after incubation with different Pt-containing drugs. The quantitative analysis of single cells and the elemental maps revealing the distribution of Pt over and within the cells provide an enhanced insight into the potential mechanism of action of these Pt-containing drugs and their efficacy against TNBC.