In order to compare wettability of electrode materials by alternative electrolytes fur molten carbonate fuel cells, contact angles were determined on Ni (in Hz-containing atmosphere) and on NiO (in O-2, CO2, and 0.33 O-2 + 0.67 CO2 atmospheres). The results are compared with ones obtained on Au (as reference material) in our previous study. NiO was used under two forms, as a thin layer deposited on Au by ion sputtering and as lithiated single crystal. Concerning the melt basicity influence on contact angle values, a consistent conclusion may be formulated on the basis of results obtained on Au, as well as on Ni (reducing atmosphere) and on NiO (oxygen atmosphere): wettability of these solids by Li/Na carbonate melt is worse than by other ones. Another behavior has been found under CO2-containing atmospheres which is an object of discussion. In all experiments, decreasing of contact angle values with temperature has been proved.