[en] In 1974-1975, the occultation of Crab Nebula by the moon occurred, which was observed in various parts of the world to study the X-ray source structure of the nebula. The X-ray from Crab Nebula is generally considered to be synchrotron radiation due to the high-energy electrons similarly to the radio waves and the light. In order to examine the structure in hard X-ray region particularly, the observation was made with two balloons on January 24, 1975. The dimension in the hard X-ray region (average 50 KeV is from 1/2 to 1/3 of 100sec in the several kev region. The center position of the hard X-ray source does not coincide with the pulsar. (Mori, K.)