The vortex pinning mechanisms of the Ba0.72K0.28Fe2As2 single crystal are studied systematically as a function of temperature and magnetic fields. The current density Jc was obtained from the width ∆M of the magnetization loop using the Bean model. The temperature dependence of the critical current density, Jc (T), was analysed within the collective pinning model at different magnetic fields. It was found that both the δl, i.e., pinning associated with charge-carrier mean free path fluctuation, and the δTc pinning mechanism, which is associated with spatial fluctuations of the transition temperature, coexist in the Ba0.72K0.28Fe2As2 single crystal in field smaller than 4 T. Their contributions are strongly temperature and magnetic dependent. At lower temperature and B ≤ 4 T, the δl pinning is the dominant mechanism, and its contributions decrease with increasing temperature. At temperatures close to the critical temperature, however, there is evidence for δTc pinning. At the magnetic fields larger than 4 T, the δl pinning mechanisms is only effects

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