To celebrate the year of centennial of X-ray discovery, we have to consider future development of radiology in 21st century. Since WC Röntgen discovered X-ray in 1895, the radiological science have been continuously expanded. Even reviewing the history of radiology in Japan, there have been several epoch-making masterpieces. We Japanese radiologists should be more proud of Japanese radiology. It is evident that radiology of the 21st century will develop more and more on the basis of computer technology. In clinical radiology, every procedure will become more rapid and non invasive, and imaging diagnoses cover not only morphology but also function of tissue and/or cell components. To foresee the future, it is essential to understand radiology in the past and the present. In this lecture, I have reviewed a history of radiology in Japan, clarified the problems at the present and emphasized the importance of computer skill. I would like to ask all of Japanese radiologists to march forward in the midstream of medical science in cooperation of Japanese society of Radiological Technology and Industries.