We study a class of typical Hartogs domains which is called a generalized Fock-Bargmann-Hartogs domain $D_{n,m}^p\left(\mu \right)$. The generalized Fock-Bargmann-Hartogs domain is defined by inequality ${\mathrm{e}}^{{\mu \parallel z\parallel }^2}{\sum }_{j=1}^m{\left|{\omega }_j\right|}^{2p}<1$, where $(z,\omega )\in {ℂ}^n\times {ℂ}^m$. In this paper, we will establish a rigidity of its holomorphic automorphism group. Our results imply that a holomorphic self-mapping of the generalized Fock-Bargmann-Hartogs domain $D_{n,m}^p\left(\mu \right)$ becomes a holomorphic automorphism if and only if it keeps the function ${\sum }_{j=1}^m{\left|{\omega }_j\right|}^{2p}{\mathrm{e}}^{{\mu \parallel z\parallel }^2}$ invariant.