Ultrasonic water processing is recognized as an emerging technology that has shown promising results for hydrogen production. It is also known that numerous parameters affect the sonication process, such as the ultrasonic efficiency, acoustic pressure distribution, input power, and the consequent cavitation activity. However, the current efficiency of such a technique limits its scalability for industrial production. Therefore, in this study, different sonoreactor geometries are developed, and a comprehensive assessment is probed to validate their performance. The study considered the effects of the geometrical parameters, such as the sonoreactor geometry, wall boundary conditions, and the number of sonotrodes. The results show that a slight change in the sonoreactors' vessel geometry while maintaining all other parameters constant significantly affects the reactor's pressure field distribution. The vessel geometry with a concave bottom wall has recorded the highest magnitude of the negative pressure, leading to more efficient cavitation bubbles. In contrast, the vessel geometry with a conical shape recorded the worst performance. On the effect of the number of sonotrodes, an eigenfrequency analysis is performed to check the excitable acoustic modes and frequencies to trigger resonance condition; the resonance condition will enhance the sonohydrogen process accordingly. The present study performs a hydrogen quantification analysis where the effects of increasing input power and maneuvering the geometrical effects are investigated. The maximum hydrogen production is recorded at 300 W in the amount of 2.5×10−9 mol/J when increasing the input power to one sonotrode mounted in a typical sonoreactor cylindrical shape at an energy conversion efficiency of 23%. For the study on the multiple sonoreactor, the amount of hydrogen produced is 308×10−9 mol/kWh at 180 W with an energy conversion efficiency of 33%.