This work aims to study the corrosion behavior of two alloys Fe-35Ni-22Cr and Fe-17Ni-17Cr in acid pickling solutions. The corrosion behavior of two alloys in HCl and H2SO4 was studied using the weight-loss method and potentiodynamic polarization, at a different time at 30 °C, 40 °C and 60 °C. The morphology of two alloys was analyzed by scanning electron microscope (SEM) and energy dispersive X-ray (EDS) analysis. The effect of temperature at constant acid concentration solutions has a strong influence on the corrosion rate of two alloys Fe-35Ni-22Cr and Fe-17Ni-17Cr. The activation energy (𝐸𝑎), enthalpy (∆𝐻), entropy (∆𝑆) and free energy (∆𝐺) were calculated and discussed. Results obtained from weight loss and potentiodynamic measurements were in good agreement and confirmed that Fe-35Ni-22Cr alloy is a higher corrosion resistance than Fe-17Ni-17Cr alloy in HCl and H2SO4 acid solutions.