Radiographic diagnosis plays an important role in bone and joint infection management but the techniques used do not all present the same interest. Conventional radiography may not be informative during the first weeks and ultrasonography is especially useful to show accumulation of intra articular fluid or edematous soft-tissue. Computed tomography, magnetic resonance imaging, bone scintigraphy are the best exams for this diagnosis. According to the type of infection (septic arthritis, osteomyelitis, spondylodiskitis, diabetic foot, prosthetic joint infection), and to anatomical localization, the examination is chosen depending on its sensitivity and its specificity for bone and joint infection management.