The title complex (Et4N)2[Fe2S2Br4]was obtained from a reation system of VS/FBr2/imnt2/Et4NCl.It crystallizes in the monoclinic space group P21/n,with a＝0.91193(2),b=1.03874 c=1.54360(1)nm,β＝105. 090(1),ν=1.4177(5)nm3,ｚ＝2,Dc=1.778g/cm3, F(000)=748,R1=0.0287 and wR2=0.0640 for 1617 reflections with I>2.0σ(I).The cluster anion [Fe2S2Br4]2 contains a rhombic Fe2S2 unit in which the geomrty of the Fe sites deviates obviously from the idealized Td symmetry leading to a D2h symmetry for the cluster anion. Meanwhile,an irregular variation was observed for Fe--Br bond distances in the complex.

Key words: IRON COMPLEX, SULFIDE, CRYSTAL STRUCTURE, BROMINE COMPOUNDS, QUATERNARY AMMONIUM COMPOUNDS