The response time of liquid crystal is a significant parameter to describe the performance of liquid crystal display. It is important to study the influence of driving voltage on the response time of liquid crystal to determine the optimal operating voltage of LCD. In this study, the calculating equation of the rising and decline time of the director under strong and weak anchoring conditions is determined by theoretical analysis. The range of driving voltage is determined according to the electro-optic effect curve, and the response time variation feature in the range of driving voltage is analyzed. The results show that for the liquid crystal used in this study, the response time increases first and then decreases with the increase of driving voltage, the inflection point is about 3V; with the increase of driving voltage, the falling time has the characteristics of inverse ratio of driving voltage, while the rising time has obvious sectional characteristics. In the range of 2-2.5V, the rising time is almost unchanged, and then increases in the range of 2.5-5V. Combined with the dynamic response process of liquid crystal molecules under the driving voltage, the reason why the rising time presents piecewise characteristics can be explained by simulating the calculation equation of the rising time and falling time of the directional vector under strong and weak anchoring conditions.