Abstract: The various embodiments herein provide a method of preparation nanosized amorphous compound ZnO/SnO2 photocatalysts. According to one embodiment herein, the nanosized amorphous compound ZnO/SnO2 photocatalysts are synthesized through coprecipitation method using NaOH as coprecipitant. According to one embodiment herein, nanosized amorphous compound ZnO/SnO2 photocatalysts are synthesized also by another method with molar ratio of 2:1 in ethanol solvent. Nanosized compound ZnO/SnO2 photocatalysts synthesized are for use in treatment of organic wastes by converting the carcinogenic compounds to harmless compounds. The obtained nanosized compound ZnO/SnO2 photocatalysts are of more equal unit. According to another embodiment, a method of preparation of nanosized compound ZnO/SnO2 photocatalysts wherein the degradation rate constant of the Acid Red 27 (AR27) having a fixed rate of the nominal speed of synthetic photocatalyst is improved by 8 times approximately.