In this paper, the crystallographic and magnetic structures of intermetallic compound Pr2(Fe0.8Co0.2)14B studied by neutron powder diffraction are reported. This compound crystallize in Nd2Fe14B type tetragonal structure, a = 8.8110?, c = 12.2307?. Assumming ferromagnetic spin configuration and easy magnetization along c axis and equal magnetic moment for Fe and Co atom on the same site, profile refinement of the measured neutron diffraction data gives the magnetic moments on two non-equivalent Pr sites Pr4f and Pr4g as 1.2 and 1.4 μB, and moments on six non-equivalent transition metal ion sites T16k1 T16k2, T8j1, T8j2, T4e, and T4c as 2.2, 2.1, 1.9, 3.1, 1.6 and 1.0 μB. Substituted Co atoms are distributed randomly among six non-equivalent sites, no preferred site occupation was observed.