Postoperative fever after cardiac surgery is a common occurrence. Most fevers are benign and self-limiting resulting from inflammation caused by surgical trauma and blood contact with cardiopulmonary bypass circuit resulting in the release of cytokines. Only a small percentage of time is postoperative fever due to an infection complicating surgery. The presence of fever frequently triggers a battery of diagnostic tests that are costly, could expose the patient to unnecessary risks, and can produce misleading or inconclusive results. It is therefore important that fever be evaluated in a systematic, prudent, clinically appropriate, and cost-effective manner. This article focuses on the current evidence regarding pathophysiology, incidence, causes, evaluation, and management of fever in postoperative adult cardiac surgical patients.