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Regarding TEXTOR and ITER-FEAT fusion devices, the net sputtering erosion rate of C targets exposed to their edge fusion plasmas has been investigated using a simulation code for plasma surface interactions, EDDY. The influence of the transport of chemically eroded CD 4 molecules on the net erosion rate is presented. Emphasis is put on the difference in the simulated results between the CD 4 reaction chain with e À , the CD 4 reaction chain with e À plus D þ , and the sticking coefficients of CD x locally returned back to the targets, which are related closely to the local redeposition, for a variety of plasma densities and temperatures. In particular, at a high density such as 10 19 m À3 and low temperatures of less than 10 eV, the net erosion rate is found to be suppressed by a significant contribution of the local redeposition resulting from the charge exchange reactions of CD x with D þ if all the locally returned CD x radicals stick. For the ITER-FEAT divertor plasma, the profile of the net erosion rate along the outer vertical target is significantly changed by the C impurity concentration in the plasma, which is eroded from other wall surfaces and then transported by the plasma. For the D þ plasma exposure only, the net erosion rate is highest around the separatrix strike point. On the other hand, it is highest at the private plasma region if a few percent of the C impurity concentration is added to the D þ plasma exposure. The local redeposition resulting from the charge exchange reactions significantly suppresses the net erosion rates at these plasma regions, but does not bring about a significant change in the erosion/deposition profile along the outer vertical target.