Meter wave radar is characterized by the natural anti-stealth and anti-radiation missiles, but is wide in pitch dimension beam, there is a possibility of the beam hitting the ground in detecting low altitude targets, and the existence of multipath effect seriously affects the height measurement accuracy of meter wave radar. The classical mirror multipath propagation signal model of uniform linear array meter wave radar is utilized for summarizing three height measurement methods based on generalized multiple signal classification (MUSIC) algorithm, i.e. the height measurement method based on improved generalized MUSIC algorithm, the joint estimation method of low elevation and multipath attenuation coefficients based on generalized MUSIC algorithm, and the Height measurement method of generalized MUSIC algorithm based on reasonable weight. Based on the analysis of the above algorithms, an accurate altitude measurement method is proposed based on synthetic steering vector generalized MUSIC algorithm for horizontally polarized meter wave radar.the simulation experiment is compared with the third height measurement method with the best performance, and a general conclusion is drawn based on the analysis of the influence of target elevation, signal to noise ratio, snapshot number, amplitude phase error, ground reflection coefficient and other factors on the height measurement performance of low altitude targets, which proves the superiority of the new method.