A retrospective cohort study included 171 patients with sepsis, stratified into septic shock (n=49) and sepsis without shock (n=122) for severity assessment, as well as improved prognosis (n=127) and poor prognosis (n=44) according to hospitalization outcomes. At admission, serum levels of procalcitonin (PCT), D-dimer (D-D), and lactate dehydrogenase (LDH) were significantly higher in the septic shock group than in the non-shock sepsis group (all p < 0.01). Multiple logistic regression showed that increased levels of PCT (OR=1.015, 95% CI: 1.002–1.028), D-D (OR=1.087, 95% CI: 1.010–1.170) and LDH (OR=1.265, 95% CI: 1.057–1.516) were independently associated with a higher probability of septic shock. Patients with a poor prognosis had persistently elevated levels of all three biomarkers during hospitalization, whereas these levels decreased significantly in patients with an improved prognosis. PCT, D-D, and LDH serve as valuable biomarkers to stratify the severity of sepsis and predict clinical outcomes. Levels of these biomarkers at admission are independently associated with the development of septic shock, and their dynamic changes provide additional prognostic information.