The uniform heat treatment of direct chill continuous casting Al-Si/Al-Mn clad slab was investigated with different temperatures and time, and the microstructure, hardness and solute distribution of the uniform heat treated samples was studied. The results show that the coarse net-work compounds of Al-Si alloy change into spot and short-bar compounds, the Mn element distribution is more uniform, and the interface of Al-Si/Al-Mn clad slab is clearer because of element solution. The hardness of Al-Si alloy is reduced after the treatment, but the hardness of Al-Mn alloy is not sensitive to temperatures and time of the uniform heat treatment. The elemental EPMA mappings show that the distribution of solute elements are more uniform, and elements are diffused on the interface of Al-Si/Al-Mn clad slab, especially Mg element becomes not obvious on the interface after uniform heat treatment. It can be concluded that the best Al-Si/Al-Mn clad slab is obtained when the uniform heat treating temperature is 480 oC and the time is 15 h.