Magnetic flux leakage (MFL) detection technology， renowned for its high reliability and non-contact detection capabilities， is widely applied in safety detections of petrochemical storage tanks and pipelines. Firstly， the theoretical development and technical principles of MFL detection are introduced. Then， the research status of defect identification， quantitative analysis， and inversion methodologies in MFL technology are explained in detail. Finally， a summary is provided， highlighting the challenges faced by current artificial intelligent methods in this field.