AbstractBased on three‐component absolute geomagnetic survey data and by use of the Taylor polynomial method and the spherical cap harmonic analysis method, the Taylor polynomial models of the geomagnetic field (X, Y and Z) and spherical cap harmonic models of the geomagnetic residual field (∆X,∆Y and ∆Z) over the Qinghai‐Xizang plateau are calculated, and corresponding theoretical geomagnetic maps are also constructed. The effects of geomagnetic anomalous stations on the geomagnetic field model are analysed, a comparison between the polynomial model and the spherical cap harmonic model of the geomagnetic field is carried out, and the boundary effects of the geomagnetic field model are discussed, too.