In the present work, spin coated thin films of P3HT: NTCDA donor- acceptor blends of weight ratios 3:1, 1:1 ,1:3 are prepared in Toluene using the self-made spin coating machine. The experiment is focused to optimize the P:N weight ratio of the photoactive blend that can absorb maximum solar energy and also to enhance the absorption by doping it with gold nano particles. Absorption property of the samples are studied using JASCO UV VIS 670 spectrometer which shows that 1:3 blend has the broad spectral response and considered to be the best active blend. The optical band gaps of the samples are determined through Tauc’s plot, wherein the onset wavelength for 1:3 sample is found to be 660nm with a band gap of 1.87 eV. The optimized 1:3 blend is doped with gold nano-particle dispersion in citrate buffer. The absorbance gets increased on doping with nano particle with extremely broadened spectral response which is attributed to the Localized Surface Plasmon Resonance(LSPR). Photons are trapped by the gold particles in the polymer matrix for the efficient harvesting of the solar energy. The construction of the solar cell using this Plasmon enhanced photoactive material is the work under progress. Copyright © 2017 VBRI Press.