Tuberculosis is a chronic infectious disease characterized by a granulomatous type of inflammation. It can occur either as a latent infection, LTBI or active disease, TB. It most commonly affects the lungs but can affect all organs in the body. Children under 12 months of age and immunocompromised children are particularly prone to disseminated infection. Paucibacillary forms are common at paediatric age, which is why the diagnosis of tuberculosis in children is a diagnostic challenge. Anamnesis, physical examination, tuberculin test, IGRA tests, conventional bacteriological diagnostics, newer molecular methods such as Xpert MTB / RIF test and radiological imaging methods are important in diagnostics. In children, tuberculosis often cannot be confirmed bacteriologically, either conventionally or molecularly, but is a clinical diagnosis based on anamnestic data, physical examination, and radiological findings. Timely diagnosis of tuberculosis is important for the prevention of complications, dissemination of the disease and for the possibility of timely and targeted treatment.