Abstract: As one of key devices in marine geophysical surveys, marine gravimeter can generate various systematic and random errors due to several factors such as external conditions and the level of on-site operators. Moreover, the scale values of the gravimeter can be also changed during the survey period. Based on the model of the gravity data collected by the gravimeter from the departure/return port and the replenishment port, an error compensation correction model is established to compensate for the observed gravity value. The scale value is calculated based on the relationship between the compensated gravity observation value and the absolute gravity value. Based on this, multiple iterations are used to obtain updated scale value until the absolute value of the difference between the scale value obtained in two adjacent iterations is less than the allowable error, thereby obtaining the corrected scale value. This method can eliminate some systematic errors caused by scale value errors and obtain high-precision ship-borne gravity data, which is of great significance for marine geophysical surveys, especially for marine gravity measurements during ocean surveys.