Abstract The crystal structure of the title compound has been determined by means of X-ray diffraction. The space group is P\bar1 with a=11.665(4), b=8.775(4), c=7.092(2) Å, α=95.73(3), β=84.36(3), γ=104.90(2)°, and Z=2. The structure was refined to R=0.048 for 1770 reflections collected on a four-circle diffractometer. The thietane ring is puckered with dihedral angles, C(2)SC(4)/C(2)C(3)C(4) and SC(2)C(3)/SC(4)C(3), of 150.1° and 149.9° respectively. The conformation of the C–Cl bonds with respect to the thietane skeleton is (3e4e), consistent with that in solution derived from the dipole moments. The average distance of the two C–Cl bonds is 1.781 Å. The C(2)–S, C(4)–S, and C(2)–C(3) bond distances are 1.872(4), 1.811(5), and 1.545(6) Å respectively; agreeing well with the corresponding bond distances observed in the cis isomer of the compound; however, the C(3)–C(4) of 1.506(6) Å is much shorter. The bisector of the bond angle formed by the ring substituents at each of the ring atoms is tilted out of the corresponding CCC or CCS planes within the thietane ring so as to increase the staggering of the neighboring substituents. The angle of tilt at Cβ is larger than those at the Cα’s. The intermolecular S···S contact of 4.080(5) Å is normal in view of the usual van der Waals radii.