The data of an ocean color sensor is abnormal. There are many irregular strips in the retrieved products. Analy- sis of a large set of data confirms that the data abnormality is mainly due to the influence of clamping (zero-voltage fluctua- tion) on each waveband. Thus, a method based on clear water free network adjustment was put forward for repairing the clamping. Then, the clamping repair method was applied to the remote sensing image and the chlorophyll concentration was retrieved from the clamping repaired image. The retrieved products have excellent uniformity and abundant detail. Finally, the comparison between the retrieved and MODIS/Aqua products demonstrates that the clamping repaired signal is right. It provides a new method for the clamping repair and a support for the quantitative application of ocean color sensor.