PURPOSE: To provide a maintenance control system capable of carrying out an accurate and quick maintenance in a synthetic fiber production line of a draw false-twist texturing machine factory.

CONSTITUTION: A data collecting device 27 relating to synthetic fiber qualities and one 28 relating to end breakage data until packaging are installed in a synthetic fiber production line which forms packages by winding on each spindle as in a spinning and winding machine factory, a draw false-twist texturing machine factory, etc., and a computer 54 which displays data on each spindle with the passage of time by calculating the ratio of quality acceptance and the ratio of full spindle formation based on data from the devices is installed to provide a maintenance control system.