In this paper, the magnetohistory effect of Pr 2 Fe 1 7 - x Mn x (x=1-9) compounds was studied. The zero-field cooling thermomagnetic curves M Z F (T) of the compounds show a strong decrease below T C with decreasing temperature. The peak temperature T P decreases nearly linearly with increasing Mn substitution. Considerable magnetic hardness is also present at low temperature, which can be attributed to the presence of narrow Bloch walls. The coercivity mechanism is due to domain wall pinning effect, which is demonstrated through the initial magnetization curves. The temperature dependence of H c is represented quite satisfactorily by a formula derived by Egami. The deduced domain wall energy density γ and domain wall width δ are 19.2x10 - 3 J/m 2 and 14.4 Å, respectively.