In this study, the corrosion behaviour of cobalt and nickel in 0.5 M H,SO4 containing pro-pargylic alchol (PA) Solutions was investigated. The current density-potential curves were ob- tained by using electrochemical potentiodynamic (1 mV.s" ) and galganostatic large and small signal pulse polarization techniques. Corrosion rates were determined by extrapolating the ano- dic Tafel lines and using potentiodynamic (1 mV.s-1) and galvanostatic small signal pulse po¬larization techniques by applying the Stcrn-Geary equation. It has been observed that propargy¬lic alcohol has a very good inhibiting effect on the corrosion of cobalt.