The constructions and major characteristics of recent stroboscopic x-ray generators and their applications to high-speed radiographies including biomedical applications are described. The generators are as follows: (a) a 100 kV generator having a fixed-anode radiation tube, (b) a 120 kV medical generator with a rotating-anode tube, and (c) a 300 keV generator utilizing a fixed-anode tube. The type (a) and (b) generators employ large-capacity condensers of about 500 nF, and the electric charges in the condensers are discharged repetitively to each tube by controlling the grid voltage. The x-ray duration can be controlled from 0.01 to 1.0 ms, and the intensity increases with increases in the charging voltage, the duration, and the filament voltage. When the external triggering system is employed, the maximum repetition rate has a value of 50 kHz. Next, the type (c) generator has a high-voltage transformer and produces short x-ray pulses with widths of about 300 ns, and the maximum rate is about 1 kHz. The high-speed radiography was performed using a film-less computed radiography (CR) system, and stop-motion images of objects were obtained.