Abstract: Fluorine-modified Ni-Mg-Al mixed oxides (Ni/Mg/Al/O-F) prepared from thermal decomposition of hydrotalcite-type (HT) precursor was characterized by XRD, SEM, CO₂-TPD, H₂-TPR, and N₂ sorption and used as catalyst in partial oxidation of methane (POM) to syngas. The results indicated that Ni/Mg/Al/O-F catalyst after calcination takes the mesoporous structure of periclase. Compared with the non-modified Ni-Mg-Al mixed oxides (Ni/Mg/Al/O), Ni/Mg/Al/O-F exhibits lower surface area, lower crystallinity and smaller particle size, but higher basicity of moderate and strong intensity. Ni/Mg/Al/O-F exhibits high activity and stability in POM; the activity at 1053K retains without deactivation even after 120h on stream. The presence of the F-anions can enhance the dispersion of active nickel species and their resistance to coking, which may contribute to the high performance of Ni/Mg/Al/O-F catalyst.