Environmental impacts, energy applications, photocatalysis on semiconductor-based hybrid materials has drawn a lot of interest recently. Having a gap in between 1 and 2 eV, the Transition Metal Dichalcogenide (TMDSc) group of materials can be good option for a two-dimensional material. A straightforward microwave synthesis technique was used for synthesizing CdS/MoS2/rGO ternary composite SEM images and XRD analysis revealed the presence of CdS/MoS2/rGO in the nanocomposite particles. The crystal structure of CdS and MoS2 is hexagonal. In terms of wavelength, the greatest absorption peak of CdS is 514 nm, and its bandwidth is 2.42 eV, whereas MoS2 band width is between 1.8 - 1.9 eV. The size of CdS is 1 nm and MoS2 is 500 nm. The average size of the nanocomposite was 1 nm. In the present work the photocatalytic activity of sunset yellow dye is checked by ternary composite nanoparticles of CdS under visible light irradiation. The photocatalytic activity is determined by various factors like effect of catalyst in which amount of catalyst varies, effect of different pH, variation in the conc. of dye and the effect of different temp. As the time interval rises by 180 min from 10 min, the dye's degradation efficiency enhances from 33% to 95%.