Ground fissures are a serious geological disaster. The ongoing construction of the Nema railway is through the active the East African Great Rift Valley segment，Many ground fissures were observed along the railway. In order to find out the development character of the ground crack in the study area and to clarify the cause of the crack of the rift in the East African Great Rift Valley of the Nema railway, this paper makes a comprehensive exploration of the geological-geophysical interpretation by means of the exploration techniques such as the comprehensive geophysical techniques and the drilling, and the results show that: The development of the crack in the East African Great Rift Valley section of the Nema railway has the characteristics of small cutting development width, shallow depth and short extension length. Drilling and shallow geological-geophysical structure investigation show that the basement of the East African Great Rift Valley section of the Nema Railway is composed of volcanic tuff lava flow and crack valley clastic rock interbedded, with a buried depth of 36 m-50 m. Through the analysis of the distribution of the pre-existing and newly-generated cracks in the study area, the formation of the ground crack is usually associated with the normal fault of the base, which indicates that the formation of the ground crack is controlled by the deep extension tensile stress; the satellite data shows that the new ground fissure develops after the heavy rain, and is in symbiosis with the deep fracture, Most of the cracks terminate in the vicinity of the roadbed where the compaction strength is large. It is shown that precipitation is the driving force of the reactivation and expansion of ground fissures, and the reinforcement of surface geological conditions is conducive to hindering the further development of ground fissures and providing theoretical support for the protection of ground fissures disasters in the study area.