Abstract: The testing data of ship-models calibrating speed were handled by dotting and lining in a coordinate paper artificially before now. This method not only takes time and labour, but also the precision is not high, and the calibrating curve would bring certain errors in the after ship-model experiments. For overcoming the above mentioned short-comings， the testing data of ship-models calibrating speed may be fitted by computer, in which some abnormal testing data also modified. So the method can improve ship-model testings precision and reliability.