Abstract: In order to accurately measure the workplace \dotH'\left(0.07\right) in real time, the ZF-FD7 online \dotH'\left(0.07\right) monitoring system was developed. Its detector is based on plastic scintillator and SiPM, and the developed intermediate machine and upper computer have data transmission, dose rate display, over-threshold alarm and other functions. For the developed on-line \dotH'\left(0.07\right) monitoring system, the radiation characteristics measured by reference to GB/T4835.1-2012 are as follows: in the range of 76 μSv/h-1.4 Sv/h, its relative inherent error is within ±10%; The average energy of the β ray is 60-800 keV, and the response is within the range of 0.8-1.2; At −45°- 45º incidence, the response of the incidence angle is between 0.88-1.00; The repeatability of the measurement results in a 1 mSv/h radiation field is 2.0%. After temperature compensation, the response change is 0.91-1.08 within −10 ℃- 40 ℃, and 0.93-1.00 in the range of relative humidity of 45%-85%. The test results show that the characteristics of the ZF-FD7 on-line \dotH'\left(0.07\right) monitoring system meet the requirements of GB/T4835.1-2012, and can be used for real-time monitoring of directional dose equivalent rate in high weak penetrating radiation sites