The peak of COVID-19 infections in China has just passed, and symptomatic manifestations in patients vary widely, with a minority experiencing severe morbidity and mortality. Early detection of adverse outcomes remains critical for clinical governance and prognosis in COVID-19. This review synthesized both national and international studies relevant to the prognostic evaluation of COVID-19 and summarized the prognostic implications of demographics (age and gender), specific laboratory parameters, adjunctive examination results, complications, and comorbidities in COVID-19 patients. Pertinent laboratory parameters chiefly included markers of inflammation, coagulation function, and electrolytic balance. Adjunctive examinations included thoracic CT and electrocardiographic evaluations. Major complications and comorbid conditions included thrombotic episodes, co-infections, secondary infections, chronic pulmonary disorders, cardiovascular diseases, acute and chronic renal diseases, diabetes mellitus, and cerebrov