Sepsis is a life-threatening syndrome characterized by a dysregulated host response to an infection resulting in multiple organ dysfunctions. Early diagnosis and management of sepsis is key to improve patient outcome but remains challenging. Despite extensive research, only few biomarkers have so far proven to be helpful in the diagnosis of sepsis. A novel protein biomarker, the pancreatic stone protein (PSP), is showing great promises. Several lines of evidences suggest that PSP has a higher diagnostic performance for the identification of sepsis than procalcitonin and C-reactive protein, and a strong prognostic value to predict unfavorable outcome at admission to intensive care unit. This review summarizes the current knowledge on the molecular mechanisms of PSP function and the clinical evidences available to highlight the relevance of this protein in the diagnosis and prognosis of sepsis.