The single crystals of eletriptan hydrobromide for two polymorphs and were developed to study their structural properties. The forms crystallized in monoclinic system with noncentrosymmetric space group. The molecular structure confirms eletriptan to exist as a hydrobromide salt in 1:1 ratio. In -form, the indole nitrogen participates in intermolecular hydrogen bonding with O=S=O, the bromine anion forms a bond only with nitrogen of pyrrolidine moiety. Whereas in -form, the bromine anion forms a bond with the nitrogen of pyrrolidine and also to indole nitrogen (N2HBr ... N1H). The two and polymorphs exhibit conformational polymorphism. The polymorphs of eletriptan hydrobromide also showed different solid state characteristic properties confirmed by using different solid state techniques such as the powder X-ray diffraction, Single crystal analysis, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), FTIR, and microscopy as well as variable humidity and temperature powder X-ray diffraction (VTPXRD).