The variation of electrical resistivity rho with temperature T for the decagonal phase of the Al₇₂Mn₂₂ has been measured in the temperature range 300-680 K. The rho -T variation exhibits two main characteristics. One relates to the negative slope in sharp contrast to the corresponding crystalline phase. Evidence and arguments have been advanced to show that the effective transport mechanism in the temperature region studied is thermally activated hopping. The other observed characteristic relates to the possible fine structure in the rho -T curve, which may be expected to reflect the expected fine structure in the density of states of the quasicrystalline phase.