Structural and magnetic properties of 2 at% Mn doped ZnO samples with 48 and 96 hours of milling time were investigated. Structural analysis indicates typical wurtzite structure with greater Mn incorporation in case of 96 hours milled sample. The field dependent magnetization (M-H) measurements confirm ferromagnetic (FM) nature of both the samples. The tendency of variation of saturation magnetization (M_S) with temperature for both samples is expected; however remanent magnetization (M_R) and coercivity (H_C) follows an interesting trend with temperature change. The comparatively higher values of M_S, M_R and H_C in case of 96 hours milled sample throughout the temperature range from 5K to 300K has been correlated with greater substitutional Mn incorporation in the host ZnO lattice.