A solid state microwave assisted technique was used for facile and eco-friendly synthesis of silver/nickel substituted salt of phosphomolybdate nanoparticles. This solid phase reaction was promoted using urea as organic driving agent under microwave treatment with the power of 360 W for 7 min. The structural and morphological characterizations revealed the formation of mixed silver/nickel ammonium salt of phosphomolybdate with Keggin-type structure and uniform nano-sized particulate morphology with the average size about 41 nm. The experimental strong point of this strategy is the use of a facile, one-pot and solid state method for synthesis of nanomaterials at short time without any acidic conditions. As a result, this method can be proposed as an instrumental way to fabricate various macromolecules of polyoxometalate in nanoscale.