Influence of using different layer thickness in three dimensional printing process of calcium sulfate based sample prior to phosphorization process was studied. Phase composition and mechanical properties of the resulting structure were characterized by x-ray diffraction and three-point bending techniques. It was seen that transformation rate, phase composition and flexural strength were all affected by the change in layer thickness. Too high layer thickness, 0.2 mm, caused the disintegration of sample during phosphorization while too low layer thickness, 0.08 mm, decreased the transformation rate. The optimised layer thickness in this study which gave both high conversion rate and flexural properties was found to be 0.1 mm.