Tin chalcogenides with different morphologies were prepared from stannous oxalate acid chalcogen through one step using ethylenediamine as the solvent. Orthorhombic SnS and orthorhombic SnSe crystals are plate like and rod like, whereas cubic SnTe particles are much smaller and appear to be spherical. Taking SnSe as a representative, the formation mechanism of these crystals was discussed,