In this study, we combined the noble metal Ag and NGP into SnO2 nanoparticles to enhance its photocatalytic performance. The effect of the incorporation of NGPs on the photocatalytic efficiency of Ag/SnO2 composites under UV-light irradiation was examined by varying the NGP content from 5 to 15 wt.%. Ag/SnO2/NGP composite photocatalysts with various weight percentages of NGP were successfully synthesized by a two-step method (ultrasonic-assisted method followed by co-precipitation method). The as-prepared composite photocatalysts were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), and UV-vis absorbance spectroscopy. According to the TGA results, the existence of NGP in the Ag/SnO2/NGP composite was confirmed, as revealed by the reduction of mass in the composite photocatalysts around 600°C. Other parameters such as catalyst dosage and scavenger type were also studied to determine the optimum degradation conditions. The results show that with the increase in the NGP content in the composites, the degradation efficiency in the photocatalytic activity also increased. When the NGP content was 10 wt.%, the photocatalytic degradation of MB reached a maximum value. To ensure the stability of the used catalyst, reusability tests were also carried out. Furthermore, scavenger experiments revealed that the main active species for the photocatalytic performance is the hole. Catalyst reusability tests revealed that the Ag/SnO2/NGP 10wt.% composite could repeatedly be used for up to four times without any significant change in the photocatalytic activity.