ve-assisted combustion method. The absence of surfactant/catalysts has led to a simple, cheap and fast method of synthesis of spinel nanoparticles. The as-synthesized spinel nanoparticles were characterized by XRD, FT-IR spectroscopy, HR-SEM, HR-TEM, EDX, and vibrating sample magnetometer. The formation of spinel nanoparticles was confirmed by HRSEM and HR-TEM and their possible formation mechanisms were also proposed. Powder XRD, FT-IR, SAED and EDX results confirmed the formation of pure and single cubic phase CoAl2O4 with well-defined crystalline. VSM measurements revealed that Zn-doped CoAl2O4 samples have weak ferromagnetic behavior and the magnetization values decreases with increasing the concentration of Zn 2+ ions in the CoAl2O4 lattice.