Due to the shortage of data regarding range, WER and WET values for carbon ion beams in a vast range of energies as well as for relevant dosimetric materials, in this work, firstly, depth-dose profiles and range were evaluated in liquid water, polyethylene (PE), aluminium, bone, polymethyl methacrylate (PMMA), and lead for carbon ion energies ranging 100-300 MeV using Fluka Mc code. Afterwards, following their most frequent use in dosimetric studies in hadrontherapy, we decided to calculate the WER and WET of only 3 dosimetric materials (PE, PMMA and lead). Then, we made the remark that the PE and the lead represent the least and the most difference to water with calculated mean WER values of 0.998 and 5.684, respectively. The calculated WER values were compared with MCNPX Mc code as well as the previous analytical results (NM, BK, BB, EBB). Good agreement was reached between Fluka, MCNPX and the previous analytical results. The largest discrepancy between the two Mc codes was 2.29% for lead at 250 MeV carbon ion energy and was about 2.06% between Fluka and the BB method for Lead at 270.83 MeV carbon ion energy. Based on the materials explored, the PE stayed the nearest to water with an average WER of 0.9983 for carbon ion energy ranging 100 to 300 MeV. KeysWords: WER, WET, carbon ion, hadrontherapy, Fluka, MCNPX