The thermal conductivity and the electrical conductivity of Cr75FexMn25-x(x=16,18) alloys have been measured over the temperatures range from 77K to 300K. The change of slope on thermal conductivity-temperature curve and the maximum on electrical conductivity-temperature curve have been found near the transition temperature of spin density wave type antiferromagnetism, which is related to the opening of the energy gap. Both alloys exhibit a rise in the phonon thermal eonductivity with decreasing temperature as being characteristic of umklapp processes.