The invention discloses a magnetic field measuring device posture swinging interference removal method, which comprises the following steps of measuring a reference coordinate system and a global coordinate system of a magnetic field measuring device, and an included angle, i.e., an posture angle between the reference coordinate system and the global coordinate system is measured; a magnetic vector in the global coordinate system is calculated according to the following formula: r1 to r1=[R]<-1>r2, wherein the r2 expresses a magnetic vector in the reference coordinate system; the [R]<-1> is an inverse matrix of [R]; the [R] is a rotation matrix. The method has the advantages that the magnetic vector in the reference coordinate system containing the posture swinging interference is converted into the magnetic vector in the global coordinate system containing no posture swinging interference, so that the interference caused by the posture swinging of the magnetic field measuring device is essentially removed.