Corrosive and abrasive properties of castings could be improved by addition of alloying elements, however, it may diminish other properties. Therefore surface alloying is employed to increase surface properties without affecting bulk properties. In this study surface properties improvement of gray cast iron by in mold addition of copper during casting was done. For this purpose, pouring temperature of molten gray iron and amount of copper were selected as variable parameters. Two pure copper wires with diameters of 0.4 and 0.8 mm inserted in bottom of sand molds and pouring was done in temperatures of 1240 and 1340 °C. Microstructural investigations, mechanical and corrosion properties of the samples were done by optical microscopy, x-ray diffraction method, Energy dispersive spectroscopy, wear and hardness tests and electrochemical impedance spectroscopy. Measuring of phases in specimens with 0.8 mm copper wire diameter showed that amounts of pearlite increased around 12% and graphite amounts decreased around 16% in specimen with pouring temperature of 1340 °C in comparison with corresponding base specimen. Similarly for specimens with lower copper content, pearlite amount increased 6% and graphite amount decreased 7%. Same results were attained for specimens poured in temprature of 1240 °C, where 6% increase in pearlite and 5% decrease in graphite amount for specimen contains less copper in surface and 11% increase in amount of pearlite and 7% decrease in graphite for specimen with more copper was seen. In all specimens, ferrite amount decreased after alloying in surface. In case of hardness test it was revealed that hardness in alloyed surfaces of all specimens has improved and by moving to inner layers decreased, gradually. Wear resistance of specimens with alloyed surface has improved 50% for 1340 °C and 33% for 1240 °C pouring temprature. Improving in corrosion behavior has occurred for both copper content and pouring temperatures. As a result in mold surface alloying for gray cast iron successfully was done and it has caused improving in corrosion, wear and hardness properties through increase in pearlite amount and decrease in ferrite and graphite amounts. Better condition was when pouring temperature and copper content was higher. Keywords: Gray cast iron, in-mold surface alloying, corrosion resistance, wear resistance.