Abstract: Fluid inclusions including CH₄-H₂O-NaCl system are widespread in reservoirs, and their parameters of P-V-T-x are very important for determining hydrocarbon accumulation stage and process. Since the calculation of above parameters is complicated, the automatic calculation of parameters using computer program is often used by geologists. By means of the PVTx calculation software for CH₄-H₂O-NaCl system in fluid inclusions based on Microsoft Foundation Class (MFC) program frame, the homogenization pressure in CH₄-H₂O-NaCl system in fluid inclusions are automatically calculated according to indoor temperature, homogenization temperature, ice temperature and Raman shift of fluid inclusion. The calculation results are directly showed in the P-T phase diagram and the gas-liquid saturation curve is obtained in the situation. The software in calculating is quick and perfect, and affords important consult in choosing tool and language for developing processing software of homogenization temperature of fluid inclusion.