Although precision medicine moved its first steps from genomic medicine, it has gone far beyond genomics, considering the full complexity of cellular physiology. Therefore, the present time might be considered as the "post-genomic era." In detail, proteomics captures the overall protein profile of an analyzed sample. The goals of proteomic analysis are to perform a global analysis of protein expression and function, to systematically define the role proteins in physiological and pathological condition, to increase mechanistic understanding of the biological processes and to discover new biomarkers and therapeutic targets. In this narrative mini-review, the role of proteomics is discussed with a particular focus on the few attempts of the application of proteomic platforms for the identification of new biomarkers in pituitary diseases, namely in acromegaly, GH deficiency and male secondary hypogonadism.