Wetting and interfacial reactivity between a liquid Na2O-SiO2-TiO2 based glass and iron oxide (mainly, FeOx) has been studied at temperatures ranging from 900° to 1050°C. Experiments were performed by the sessile drop technique under Ar and under air. The FeOx dissolution was observed to occur with formation of several compounds in the vicinity of the interface. The solubility limit of FeOx in the glass was determined and shown to be intensely activated by temperature. An operative mechanism of such a complex reactivity at temperatures below 950°C is proposed. A limited number of experiments were also performed with Fe2O3oxide. Experimental results clearly show that the interfacial reactivity is very different for both iron oxides and these results are discussed in relation with the possible diffusion paths issued from equilibrium phase diagrams of respective systems.