The effects of aqueous extract of Gummara of the Phoenix Dactylifera (AEGPD) and aqueous extract of Lactuca (AEL) on
the corrosion inhibition of mild steel in 1M HCl solution were investigated by weight loss measurements at temperature
range (30 – 60 ̊C). Results obtained showed that the percentage inhibition increases with the increasing of inhibitors
concentration and decreases with the increasing of temperature. At a concentration of 2 g/L, the percentage inhibition
reached about (93.82% and 95.81%) at 30 ̊C for (AEGPD) and (AEL); respectively. The thermodynamic functions of
dissolution, activation energy and adsorption processes were calculated and discussed. Adsorption of the two inhibitors was
found to follow the Langmuirs adsorption isotherm.