Infections remain a part of the natural course of cancer. During the course of their disease, patients with lung cancer frequently present with an infection that can ultimately be fatal. Pathogenesis of infectious syndromes is usually determined by the underlying disease, as well as, the iatrogenic manipulations that occur during its management. Hence, lung cancer infections include lower respiratory tract infections in the context of COPD, aspiration, obstruction and opportunistic infections due to immunosuppression. Moreover, treatment-related infectious syndromes including post operative pneumonia, febrile neutropenia and superimposed infection following radiation/chemotherapy toxicity is common. Importantly, diagnosis of infection in the febrile lung cancer patient is challenging and requires a high index of suspicion in order to distinguish from other causes of fever, including malignant disease and pulmonary embolism. Prompt initiation of treatment is pivotal to avoid increased mortality. Careful consideration of infection pathogenesis can predict most likely pathogens and guide antibiotic management, thus, ensuring most favourable outcome.