Sepsis is currently defined as the presence of organ dysfunction occurring as the result of a disturbed host response to a serious infection. Sepsis is one of the most common diseases, which cause mortality and a considerable absorber of healthcare resources. Despite progress in technology and improving knowledge of pathophysiology, the disease mechanism is still poorly understood. At present, diagnosis is based on non-specific physiological criteria and on the late identification of the pathogen. For these reasons, the diagnosis may be uncertain, treatment delayed or an immunomodulatory therapy cannot be established. An early and reliable diagnosis is essential to achieve better outcomes on disease progression. The host response to infection involves hundreds of many mediators of which have been proposed as biomarkers. There is a need for new diagnostic approaches for sepsis, new sepsis biomarkers that can aid in diagnosis, therapeutic decision and monitoring of the response to therapy. The differentiation of sepsis from non-infectious systemic inflammatory response syndrome is difficult, and the search for a highly accurate biomarker of sepsis has become one important objective of the medicine. The goal of our review is to summarize the recent advances on the most commonly studied serum biomarkers, evaluated in clinical and experimental studies, for early diagnosis of sepsis and their informative value in diagnosis, prognosis, or response to therapy. In this context, we have tracked the clinical utility of measuring serum biomarkers, such as procalcitonin, pro- and anti-inflammatory cytokines, C-reactive protein, leptin and their combinations. Currently, has not been identified an ideal biomarker to aid in the diagnosis of sepsis. It is hoped that the discovery of new serum markers, as well as their combinations, will serve for the diagnosis and prognosis of sepsis.