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The continuous gradient porous stainless steel material was fabricated by compression moulding forming technique. The shrinkage ratio and the microstructure of the prepared samples with different thickness were analyzed. The results indicate that the continuous gradient porous samples were deformed after sintering confirmed by their geometric contour, i.e. the initial cylinder samples became truncated cone shape due to different sintering stress between the adjacent gradient layers. The stress between two adjacent layers can promote powder sintering and influences the sintering shrinkage during sintering. In particular, the smaller the particle size is, the more obvious the influence is. The proper particle size distribution and the reasonable match of the bulk or mass of powders between different gradient layers can avoid the sintering deformation and cracks by the mutual suppression of the sintering stress among the different gradient layers to realize synchronous shrank sintering.