Abstract: Background and Objective: The single crystal of ethyl 6'-cyano-7'-phenyl-1',6',7',7a' tetrahydro-3'H-spiro[indeno[1,2-b] quinoxaline-11,5'-pyrrolo [1,2-c] thiazole-6'-carboxylate (ECPTSIPTC) was crystallized by slow evaporation method after synthesis of compound. The main objective of the present study was to analyze complete vibration spectra of ECPTSIPTC compound through the FT-IR and FT-Raman techniques. Materials and Methods: Indeno quinoxaline, thioproline, ethyl cyano acetate, benzaldehyde, ethyl acetate and chloroform were used to grow the single crystal of title compound which were purchased from Sigma Aldrich company through local scientific companies in Tamil Nadu, India. The slow evaporation technique was employed to grow needle shaped ECPTSIPTC crystal using the chloroform as a solvent. Results: The vibrational spectra were recorded at room temperature using the FT-IR and FT-Raman spectrometers in the wavelength range 4000-400 cm–1. The optical property was performed by double beam spectrophotometer in the wavelength range 200-1100 nm. Conclusion: The FT-IR, FT-Raman vibrational spectral studies confirmed the various functional groups present in the title compound. The optical property of the title compound shows that the grown crystal has high transparency in the entire visible region and the energy gap was found to as 4.8 eV. Due to the wide applications of title compound in biological and pharmaceutical fields, it was considered for study in this present work.