To improve the performance of polarization navigation, a new method to calculate the heading angle using all-sky polarization pattern is proposed. Through analyzing the distribution feature of atmospheric polarization pattern, we propose a method to identify the sample points of solar meridian area, from which we can decide the azimuth angle of solar meridian in carrier coordinate by least square algorithm. The DOP distribution feature along meridian is used to distinguish the solar meridian and anti-solar meridian, thus solving the problem of ambiguity in acquiring the heading angle. And then the heading angle is figured out since we can get the azimuth angle in geographic coordinate by astronomic theory. The simulated results show that under sampling mode that we set, the error of heading angle is below 0.05°; under different simulated conditions namely different time of a day, different input heading angle and different amount of sampling points. When there is an error within 8° with angle of polarization, the average error of heading angle stay within 0.2°, thus proving the high precision and well adaptation of the method.