In　this　study,　a　new　metastable　phase　of　crystallized　MoO3·0.3H2O　nanobelts　was　successfully　synthesized　using　a　simple　synthetic　route.　The　synthesized　nanobelts　are　highly　crystalline　and　have　lengths　up　to　several　tens　of　micrometers.　Based　on　the　experimental　observations,　a　possible　reaction　model,　solid-solution-solid,　was　proposed　for　the　formation　of　the　nanobelt　structures.　©　2008　Elsevier　B.V.　All　rights　reserved.