OBJECTIVES: The main purpose of this final paper is to clearly show methods of collecting and processing samples as well as possibilities of cytodiagnostics of liquid samples. MATERIAL AND METHODS: Literature was searched by topic and subject of research, authors and journal. A targeted search was conducted on the bases of MEDLINE/PubMed, Science Direct, Google search and through scientific articles. The literature review covers the period up to 2020 and relies on publicly available databases. In studying the relevant articles, the most important results, discussions and conclusions are identified and presented in this final paper. RESULTS: Cytodiagnostics of liquid samples plays a significant role in the treatment of patients with neoplastic and non-neoplastic diseases. It is of great importance in the case of finding malignant cells in bodily fluids, especially in patients without previous diagnosis of malignancy because it indicates not only the degree of the spread of malignancy but also the possible origin of the primary tumour. For morphological analysis, liquid samples are centrifuged and standardly stained by MGG and Papanicolaou methods. The cell block method provides insight into the architecture of fragments, the correlation of histological and cytological samples and the production of samples suitable for immunocytochemical and molecular analyses. The liquid based cytology method produces a thin layer of cells with minimal overlap that greatly facilitates morphological analysis. CONCLUSION: Cytodiagnostics of liquid samples analyses peeled cells, and their processing in a cytocentrifuge gives a suspension of cells on the small area that can be morphologically analysed, turned into cell block and additional cytochemical, imunocytochemical and molecular analyses can be performed.