A novel hexangular tube structure of ZnO has been successfully synthesized via the solvo-thermal method, using Zn(NO3)(2)center dot 6H(2)O and NaOH as starting materials. The results showed that the supersaturation near the surface of ZnO crystal is higher than that inside the crystal, which leads to a preferential growth along c-axis of the side surface. The strain between the surface and the bulk of ZnO rods drives ZnO rods into tubular structure. The spectroscopic results show that ZnO tubes possess the wurtzite structure. Three emission peaks have been detected, a violet peak at about 399.9 nm, a blue emission at about 448.5 nm and a green emission at about 549.8 nm.