In this study, the corrosion behavior of 304 austenitic stainless steel was investigated in two acidic media: 0.1 M oxalic acid and 0.5 M glyoxylic acid. Electrochemical techniques including open‑circuit potential measurements (OCP), anodic potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) were employed. The main objective was to compare the corrosion rate and the passive layer formation mechanism in these two industrially relevant acidic environments, particularly for applications in the sanitary and perfumery industries. The polarization curves showed that the 304 stainless steel exhibits active‑passive behavior in both media. However, in oxalic acid, two passive regions were observed: one metastable region attributed to the formation of ferric oxalate, and a stable region due to chromium/iron oxides. In contrast, only one passive region with a wider potential range was observed in glyoxylic acid. Analysis of Nyquist and Bode plots recorded at the open‑circuit potential revealed that both systems display a single time constant, indicating that the corrosion behavior is mainly controlled by the passive layer. The polarization resistance (Rp) values derived from EIS for 304 stainless steel in glyoxylic acid (8.549E20 Ω·cm²) were significantly higher than those in oxalic acid (8943 Ω·cm²), suggesting a much lower corrosion rate in glyoxylic acid. Accordingly, it is recommended that containers made of 304 stainless steel are more suitable for storing solutions containing glyoxylic acid than those containing oxalic acid.