The research on ocean surface current sounding by along-track interferometric SAR is an important role in realizing the globalization and refinement of current information. In order to improve the iteration convergence speed and parameter retrieval accuracy of ocean surface current, the correction coefficient design problem was transformed into scale factor selection problem under constraints of the phase difference between the simulated interference phase and the measured phase difference, and radar, and platform parameter, according to the parameter characteristics of the correction coefficient to construct the constraint relation of the fitness function. The technical method was designed to calculate the correction coefficient by genetic algorithm, which was embedded in the iterative retrieval algorithm to construct a new retrieval method. The results of spaceborne SAR data simulation showed that the RMSE of current direction is better than 10.0°, and the RMSE of current velocity is better than 0.1 m/s, which meets the requirements of ocean surface current retrieval accuracy. The improved ocean surface current retrieval algorithm can reduce the number of iterations by 2 to 3, which effectively improves the retrieval efficiency. The research is of great significance to improving the effectiveness and accuracy of ocean surface current sounding by along-track interferometric SAR.