SARS-CoV-2 infection has to be confirmed by virological diagnosis. Multiple diagnostic tests are available without enough perspective on their reliability. Therefore, it is important to choose the most suitable test according to its sensitivity and specificity but also to the stage of the disease. Currently, the RT-PCR detection of the viral genome in respiratory samples is the most reliable test to confirm the diagnosis of an acute SARS-CoV-2 infection. It has to be done in Class II biological safety laboratory. However, it may lack sensitivity, particularly in the advanced phase of infection, and depends closely on the samples' quality. Rapid PCR by cartridge system reduces response times but is not suitable for laboratories with high throughput of requests. Detection of virus antigens on respiratory samples is a quick and easy to use technique; however it has not good specificity and sensitivity and cannot be used for diagnosis and patient management. The detection of specific antibodies against SARS-CoV-2 is better used for epidemiological analyses. Research should be encouraged to overcome the limits of the currently available diagnostic tests.