In research circles, there is an increasing need to seek and identify new methods in the diagnosis of pathologies, monitoring the progression of the disease and response to treatment. The sensitivity of detection technologies has improved markedly, and enables the quantification of analyses in very small quantities. Tears represent a biological material with ever increasingly developing possibilities in the diagnosis of various pathologies. Our objective was to compile a basic overview of the diagnostic potential of tears via a summary of the potential lachrymal biomarkers of various pathologies. The article contains descriptions of protein biomarkers studied particularly in recent years, which correlate with a certain ocular pathology (dry eye, allergy, glaucoma etc.). It also summarises the results published to date in the field of systemic pathologies in patients with scleroderma, cystic fibrosis, diabetes mellitus, multiple sclerosis, cancers and Parkinson's disease. It concentrates on proteomic analyses, with the aim of improving the effectiveness of markers which could be used in future also in the timely diagnosis of ocular pathologies in clinical practice.Key words: Tears, proteins, biomarker, ocular pathologies, systemic pathologies.