Nitriding process through a cyanate liquid salt bath is one of the advanced surface treatment techniques that is recently employed to modify corrosion and wear resistance behaviour of steels. Considering spreading out of P/M alloys application in various industries, especially automotive industry, and the presence of porosities in its structure, in this research the influence of porosities, process duration and temperature parameters in nitrogen diffusion and formation of layers on a P/M Distaloy AE Steel through the advanced cyanate liquid salt bath nitriding process has been investigated. Also it has been analyzed microstructure of layers by means of OEM, SEM and microhardness deep profile investigations. Existence of ε (Fe2-3N) and γ' (Fe4N) phases was detected by XRD analyzing. Results demonstrated that with increasing porosities, it was configured a non-uniform diffusion regions on the surface due to nitrogen atoms dispersion.