A positive electrode material and a preparation method thereof, a positive electrode (10), a sodium battery, and an electric apparatus are provided. The positive electrode material includes a layered oxide represented by a chemical formula NaqNixMnyFezZnpMiOj, where 0.8≤q≤1, 0.1≤x≤0.3, 0.2≤y≤0.5, 0.2≤z≤0.35, 0.02≤p≤0.075, 0≤i≤0.1, 1.8≤j≤2, x+y+z+p+i≤1, and Mis an active and/or inert doping metal element. A preparation method of the positive electrode material includes a step of performing sintering treatment on a precursor of NaqNixMnyFezZnpMiOj. The positive electrode (10) includes the layered oxide represented by the chemical formula. The sodium battery includes the positive electrode (10). The electric apparatus includes the sodium battery.