Factors affecting the stability of diaphragm wall trench have been reviewed. Measures and precautions of selecting"enhance the construction quality control","reduce the diaphragm wall construction unit pitch","no reinforcement bar overlay between diaphragm wall units to save the excavation period of trench","increase the height difference between slurry level and ground water level","grouting",etc.to provide a safety and economical counter measures are introduced through two construction cases.