This study investigates controlled optical bandgap tuning through precise adjustment of the SnO2 and MoS2 mass in nanocomposites. A sonochemical solution mixing method, coupled with bath sonication, is employed for the preparation of SnO2–MoS2 nanocomposite. This approach allows for comprehensive characterization using UV–Vis FTIR, XRD, EDX, Raman spectroscopies, and FESEM, providing insights into morphology, chemical, and optical properties. Increasing the SnO2 mass leads to a linear decrease in the optical bandgap energy, from 3.0 to 1.7 eV. Similarly, increasing the MoS2 mass also results in a decrease in the optical bandgap energy, with a limitation of around 2.01 eV. This work demonstrates superior control over optical bandgap by manipulating the SnO2 mass compared to MoS2, highlighting the complexities introduced by MoS2 2D nanosheets during sonication. These findings hold significant value for optoelectronic applications, emphasizing enhanced control of optical bandgap through systematic mass manipulation.