Macrosegregation refers to the variation of composition on a large scale across the whole cross section of casting.This defect can be very severe for large sized direct chill (DC)casting billets/ingots of high alloying elements containing aluminium alloys and cannot be removed even with long time subsequent homogenisation process, therefore have to be controlled and minimised during solidification process.Melt conditioned DC (MC-DC)casting is an emerging technology to optimise the solidification process by high shear conditioning the alloy melt in the sump during DC casting and to manipulate the solidification microstructure and composition of the resultant casting.In this paper, we report for the first time the improved macrosegregation in the MC-DC casting billet of an industrial scale in an A4xxx aluminium alloy.