Abstract: The crystal structure of ZSM-S has been determined after the 540℃ high-temperature roasting by means of the X-Ray diffraction for polycrystalline materials.The parameters of the cell are.a=20.16±0.03Å; b=19.97±0.03Å; c=13.44 ±0.02Å.Its space group is D_2h¹⁶-P_nma.The channels of the structure consist of straight elliptic channels parallel to [010] and Z-form channels perpendicular to the former and parallel to [010] The openings of the straight channel have a long axis of 5.80Å and a shcrt axis of 4.78Å.The openings of the Z-form channels are approximately n-ten-membered rings,with a diameter of 5.30Å long and a folding angle of 156°.It is concluded from the structure analysis that ZSM-5 contains a series of compounds.Having similer structural topographies.But the sizes of both channel openings and the value of folding angles of Z-form channels vary with the ratio of si to Al,crystallizing conditions and mode of postprocessing.Their symmetries can be C_2h⁵-P_21/n,C_2v⁵-P_n21a Or D_2h¹⁶-P_nma.Consequently,for structural topographies,the conclusions drawn by no are similar to those drawn by Kokotailo et al.