NiFe₂O₄ nanoparticles (< 10 nm) embedded in a NiO matrix have been fabricated by calcining the corresponding Ni^ⅡFe^Ⅲ-layered double hydroxide (LDH) precursors at high temperature (500 ℃). Compared with the NiFe₂O₄/NiO nanocomposite obtained by calcination of a precursor prepared by a traditional chemical coprecipitation method, those derived from NiFe-LDH precursors show much higher blocking temperatures (T_B) (~380 K). The enhanced magnetic stability can be ascribed to the much stronger interfacial interaction between NiFe₂O₄ and NiO phases due to the topotactic nature of the transformation of the LDH precursor to the NiFe₂O₄/NiO composite material. Through tuning the Ni^Ⅱ/Fe^Ⅲ molar ratio of the NiFe-LDH precursor, the NiFe₂O₄ concentration can be precisely controlled, and the T_B value as well as the magnetic properties of the final material can also be regulated. This work represents a successful example of the fabrication of ferro(ferri)magnetic (FM)/antiferrimagnetic (AFM) systems with high magnetic stability from LDH precursors. This method is general and may be readily extended to other FM/AFM systems due to the wide range of available LDH precursors.