An improved integral measuring method of pendulous gyroscope is developed to shorten the north seeking time and improve the measuring precision. On the rough north seeking stage

a step move method that is to consume the mechanical energy of gyroscopic pendulum by the outer action is used to realize the fast north seeking

and then

on the precise north seeking stage

a double photoelectric integral method is adopted to get the intersecting angle between the meridian plane and the reference axis of gyro. The double photoelectric integral method gets the equilibrium position of gyro swing by one and a half periods integral calculating of measuring data and then makes use of the formula to compute the intersecting angle. The experimental results show that the double photoelectric integral method can effectively improve the measuring precision and decrease the integral error of measuring period variety; the integral error is less than one of tenth that in the traditional photoelectric integral method; and the scheme satisfies the engineering requirement of accuracy and speediness basically.