Organic, environmentally beneficial, and economically advantageous chemicals known as Schiff Bases are frequently used as corrosion inhibitors for metal alloy surfaces. One such widely used alloy is mild steel, which often exhibits poor corrosion resistance when exposed to acidic conditions like H2SO4. The most recent advancement in this process is using green technologies in applying Schiff Bases. These well-known sustainable methods work well for reducing toxicity, conserving energy, and many other things. This study is an expansion of a previously published study that uses the same methodology to create a Schiff Base from gallic acid hydrazide, which is created using a different aldehyde (than used in the previous work). Microwave irradiation is utilized for heating as a green technology strategy. Then, NMR, IR, SEM, and XRD approaches are used to describe the Green Schiff base. The Schiff Base is then applied to confirm their effectiveness as metal corrosion inhibitors. To assess their ability to suppress corrosion, three methods—the mass loss technique, SEM, and potentiodynamic polarization method—are applied. The study is thought to be a step forward in the adoption of environmentally friendly inhibitors with the aim of preventing corrosion on metal surfaces.