On basis of the experience in the prefabrication of the largescale segments for the shielddriven Wuhan Yangtze River crossing tunnel, the paper presents the types of the cracks of the largescale segments, as well as the causes and countermeasures for the cracks. The paper places its emphasis on the description of the key technologies and critical technical processes of the prefabrication of the segments. The paper also presents the problems frequently encountered during the prefabrication of the segments and their prevention measures.