A new crystal structure is found to exist for stibnite which is orthorhombic, Pmmm. In this structure all the antimony and sulphur atoms have only one type of coordination, namely, trivalent and diavalent, respectively. They form a honey-comb-like planar network which is parallel to the xz-plane and stacked along the y-axis with the middle plane slightly displaced along the plane with respect to the top or bottom layer. The structural analysis based on the observed reflections in the diffraction pattern shows that the proposed structure is correct. We feel that stibnite can also crystallize and exist in this proposed new structure which is entirely different from the existing structure. The present structure can also account for the fact that this compound can transform easily from amorphous to crystalline state.