In this paper, the existence of global classical solutions is justified for the three-dimensional compressible magnetohydrodynamic (MHD) equations with vacuum. The main goal of this paper is to obtain a unique global classical solution on mathbb{R}^{3}times [0, T] with any Tin (0, infty ), provided that the initial magnetic field in the L^{3}-norm and the initial density are suitably small. Note that the first result is obtained under the condition of rho _{0}in L^{gamma }cap W^{2, q} with qin (3, 6) and gamma in (1, 6). It should be noted that the initial total energy can be arbitrarily large, the initial density allowed to vanish, and the system does not satisfy the conservation law of mass (i.e., rho _{0} notin L^{1}). Thus, the results obtained particularly extend the one due to Li–Xu–Zhang (Li et al. in SIAM J. Math. Anal. 45:1356–1387, 2013), where the global well-posedness of classical solutions with small energy was proved.
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