The ternary oxide functional nanomaterial Zn2SnO4 has been synthesized by the thermal evaporation method. The products in general contain numerous kinds of nanowires. In the present work, a remarkable type of Zn2SnO4 nanowires with a pseudoperiodical twinning structure has been investigated by transmission electron microscopy (TEM). These nanowires with a diameter of about 100 nm grow along the <111> direction. High-resolution TEM examinations suggest that a large fraction of the <111> twin boundaries are extended to a thickness of a few nanometers. The twining plane for the perfect case is localized on the Zn atom layer.