The utility model discloses a shield that can install fast constructs quick -witted hobbing cutter state on -line measuring system, including hobbing cutter detection device, data sink, control display device, hobbing cutter detection device includes the support that is connected with the girff, the apron, the battery, the the control unit module, electricity eddy current sensor module, the rotational speed sensing module, the apron is connected with the support through the bolt, the the control unit module, electricity eddy current sensor module, the rotational speed sensing module is all installed on the support, a cover plate, a battery, a control unit module, the rotational speed sensing module is connected. The utility model provides a need not to carry out the hobbing cutter state detection scheme that changes to the blade disc, the installation is simple reliable, and it is convenient to dismantle, to the present internal a large amount of earth pressure balance shield machine that exists, can use by the direct mount, has improved work efficiency, has reduced manufacturing cost.