To improve the monitoring effect of voltage stability, an online monitoring method for intelligent voltage stability of the power grid is designed based on the consideration of potential factors. First, the converter is used as a voltage detecting device to collect the intelligent voltage data of the power grid, and then the characteristic quantity of power grid voltage is extracted by using the wavelet change method. Based on the practical criterion of voltage instability of smart grid, the quantitative evaluation factors that can reflect the severity of voltage instability are selected, and the voltage stability state is monitored online by wide-area measurement. The experimental results show that the proposed method has a high fitting degree between the voltage monitoring value and the actual voltage value, and the global maximum value of the transmission delay of the monitoring signal is only 90.57 ms, and the voltage identification rate can always remain above 95%, indicating that the proposed method has high effectiveness and timeliness in voltage stability monitoring. In addition, the Pearson coefficients of this method are in the range of 0.8∼1.0, indicating that the monitoring accuracy of voltage stability is higher, which proves that the design expectation is effectively realized.