By use of synchrotron radiation, the powder x-ray diffraction of the one-dimensional complex bis(diphenylglyoximato)platinum(II), Pt(dpg)(2), has been studied at room temperature and at high pressures. The lattice constants with an orthorhombic structure for Pt(dpg)(2), monotonically decreases with increasing pressure up to 10 GPa; the linear compressibility of each axis is estimated. The magnitude of the linear compressibility increases in the order c > a > b. The Pt-Pt distance along the c axis abruptly decreases from 3.50 angstrom at ambient pressure to 2.80 angstrom at around 10 GPa. A bulk modulus of Pt(dpg)2, has been obtained from the volume vs. pressure curve fitted by a Birch equation of state. The bulk modulus of this complex is very small, 7.6 GPa. Pt(dpg)(2) is the most compressible compound. The electrical and optical properties of Pt(dpg)(2) are very sensitive to pressure. These interesting behaviors at high pressure are closely related to the rapid shrinkage of the c axis with increasing pressure.