To solve the problem where a rapid change occurs during metering for obstructing quantitative metering, and metering accuracy deteriorates when winding up string that has been set to a wind-up device with quantitative metering equipment in advance by a string package to obtain a specific amount.

The quantitative metering device that has a device for winding up string by a string package for obtaining the string package with target weight is provided with a means for setting the value of the allowed amount of change in weight for winding up the string with a capacity within tolerance, a target weight- setting means, a means for setting the amount of change in weight of the string where the amount of change of the string being metered decreases within the allowed amount of change in weight as a weight value, a means for making the amount of change in weight invalid when the amount of change in weight exceeding the allowed amount of change in weight occurs, a means for adding the difference in the weight value that has occurred at that timing up to a point immediately before as an integration value when the amount of change in weight exceeding the allowed amount of change in weight occurs, starting metering when the amount of change in weight is within the allowed amount of change in weight, and ending metering when the integration value matches a target weight value.