Abstract: A micronanotube of new inorganic compound with external shape of tetra nal prism has been synthesized. It is made of transitional metal oxychloride. From SEM detection, the micronanotube has an external diameter of 100－500 nm and an internal diameter of 60－300 nm. Its wall is very thin, 20－70 nm, and its length is from a dozen micro to dozens of microns(to see Fig.1(ad)). It has been prepared by solid state reaction in a direct growth way. 　　From XRD, TEM and SEM determination, the micronanotube crystal belongs to orthorhombic system and its lattice constants are a=0.5864(2)nm, b=0.6032(2)nm andc=2.972(2)nm(to see Fig.1～2 and Table 1). It possesses semiconducting properties. From curve log(1/ρ)～1/T, its energy gap isEg≈1.2 eV(to see Fig.3). The micronanotube material will be a prospect material used as catalysts, material to store gases or energy, and material used as electrode in photoelectric cell and photoelectrolytic cell. 　　Additionally, the preparation of the micronanotube material by solid state reaction is simple in operation and cheap in cost.