The structural, thermal, static magnetic, and resonance properties of the low-dimensional NaCuFe.sub.2(VO.sub.4).sub.3 compound obtained by the solid-phase synthesis have been investigated. In the temperature range of 110-300 K, the electron spin resonance in the X band with a g factor of 2.008 has been detected. The magnetic properties of a sample with a high frustration level in the paramagnetic, antiferromagnetic, and disordered states have been examined. A shift of the Néel temperature to the high-temperature region in an external magnetic field has been observed. The origin of the disordered magnetism in NaCuFe.sub.2(VO.sub.4).sub.3 are discussed. The features of substitution of sodium for lithium on the physical properties of the ACuFe.sub.2(VO.sub.4).sub.3 (A = Na, Li) system have been established. It is shown that the chemical pressure changes the crystal lattice parameters, spacings between magnetic ions, and crystallite size, which is reflected in the physical properties of the material.