Focusing on the problem that magnetic interference of carrier in magnetic anomaly detection will greatly affect the measurement results, a carrier interference magnetic field compensation method for magnetic anomaly detection based on RLS algorithm is proposed. First, classify the interference in the magnetic anomaly detection and establish a measurement model. Then, convert the model to a standard multiple linear equation. Reduce collinearity through orthogonal and linear constraints. Solve the model parameters through the RLS algorithm and the correctness of the algorithm is verified by model simulation. Finally, carry out finite element simulation of the carrier with and without anomalies. The RLS algorithm is used to calculate the compensation parameters from the simulation data without abnormality. The calculated compensation parameters are used to compensate the abnormal simulation data. The results show that the compensation error is significantly reduced. The signal improvement ratio after compensation for experiment without magnetic anomalies is 10. 3. This method can be used for carrier interference magnetic field compensation in magnetic anomaly detection. It effectively improves the anti-interference ability of magnetic anomaly detection, and is of great significance to buried object detection, mineral exploration, anti-submarine and other works.