O-(p-tolyl)dithiophosphato nickel complex[Ni(S_2P{O}OC_6H_4CH_3-p)(dppv)]has been synthesized by the treatment of(dppv)NiCl_2(dppv=Ph_2PCH=CHPPh_2)with(p-CH_3C_6H_4O)_2P{S}SH·Et_2NH in THF.The new complex was fully characterized by elemental analysis,IR,~1H NMR,~(31)P NMR spectroscopies and thermo-gravimetric analysis.The molecular structure of the complex was established by X-ray crystallography.The crystal crystallizes in monoclinic,space group P2_1/c with a=9.2739(5),b=17.8803(8),c=20.1879(12)A,β=93.269(5)°,V=3342.1(3)A~3,Z=4,C_(33)H_(29)NiO_2P_3S_2,M_r=673.30,D_c=1.338 g/cm~3,F(000)=1392 andμ(MoKα)=0.877 mm~(-1).The final R=0.0578 and wR=0.1045 for 4138 observed reflections with I>2σ(I)and R=0.1050 and wR=0.1204 for all data.The Ni centre atom adopts a NiP_2S_2 square-planar geometry with two phosphorus atoms from the dppv ligand and two sulfur atoms from the O-(p-tolyl)dithiophosphate ligand.The most interesting structural feature of the title complex resides in its 1D helical chain structure constructing via intermolecular C-H…O secondary interactions along the b-axis.The adjacent helical chains running in opposite directions are connected into a 1D double-stranded helical chain and further linked into a 2D supramolecular network by weak C-H…C interaction.