Na+ was used as template in the synthesis of tunnel manganese oxides from a layered manganese oxide under hydrothermal conditions. Two types of tunnel manganese oxides were obtained by the hydrothermal reaction. The manganese oxide with a one-dimensional (2 x 4) tunnel structure formed, under low temperature conditions, and Na0.44MnO2 with a one-dimension complex tunnel structure under high temperature conditions. The mechanism of the transformation reaction can be explained from the structures of the products and template size.