In response to the problem of identifying low amplitude structures in the Akzor structural belt on the eastern edge of the Caspian Sea basin, a low amplitude structural identification method based on inversion layer velocity method and structural trend surface fitting method was developed. This method is suitable for situations where velocity anomalies are locally developed, velocity changes are rapid, layer burial depth in slope areas is large, and trap amplitude is small. The method of optimizing structural interpretation horizon trends and interval velocity inversion under single well velocity constraints is used to establish a velocity model for the study area and calibrate seismic horizons. This method overcomes the limitations of lateral continuity of conventional interval velocity inversion methods and has better adaptability to complex formations. The structural trend surface fitting method has effectively identified the low amplitude structures in the study area, overcoming the problems that are difficult to identify due to low structural amplitude, flat event axes, and small variation amplitude. The structural trend surface fitting method has been applied to the depth domain structural map of the eastern edge of the Caspian Sea, and good results have been achieved.