Experiments have been performed in a 10 cm ID horizontal pipeline to observe the effect of temperature, carbon dioxide partial pressure, flow, and oil/water composition, on corrosion in horizontal multiphase slug flow, using a low viscosity (2 cp) oil. Corrosion rates have been measured for water cuts ranging form 20 to 100%, carbon dioxide partial pressures of 0. 27, 0. 45 and 0. 79 MPa, temperatures of 40. 60, 70. 80 and 90 C and Froude numbers of 6, 9 and 12. The corrosion rates are found to increase with an increase in temperature, Froude number and carbon dioxide partial pressure. The corrosion rates are found to decrease with increase in oil composition. The average void fraction as well as the pressure drop across the slug is found to increase with an increase in Froude number and carbon dioxide partial pressure. A model to predict corrosion rates for low viscosity oils has been established which relates the corrosion rate to the pressure gradient, temperature, carbon dioxide partial pressure and water cut. © 1996 by NACE International.