Herein we report a 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2',3'-d']-s-indaceno(1,2-b:5,6-b'] dithiophene (ITIC) small molecule additive based bulk heterojunction (BHJ) perovskite solar cell (PSC). The BHJ PSC with 0.2 wt% of ITIC exhibits a power conversion efficiency (PCE) of 17.6% with remarkably enhanced short-circuit current of 23.7 mA cm(-2) as compared to reference PSC (without ITIC). The addition of ITIC plays an important role in improving the quality of the perovskite film like enhanced absorption, compact grains with reduced roughness (approximate to 12.3 nm), higher electron mobility (mu(e) = 1.43 x 10(-3) cm(2) V-1 s(-1)), better charge extraction and thermal stability of the solar cells. The BHJ PSC device degraded only by approximate to 18% after 53 days at 80 degrees C in atmospheric condition. In addition, several important characteristics of solar cell like current-voltage hysteresis, charge transfer, and recombination losses have been studied.