Polyaniline (PANI) when composited with bismuth selenide nanoflakes (Bi2Se3 NFs), a low bandgap semiconductor, reveals enhanced photocatalytic activity for degradation of organic dyes under irradiation of visible light. The composites synthesized using Bi2Se3NFs templates with different weight percentages of PANI by in-situ chemical oxidative polymerization have been used as efficient photocatalysts for degradation of anionic dye, Methyl Orange (MO), and cationic dyes, Rhodamine B (RhB) and Malachite Green (MG). Based on radical trapping experiments, the mechanism for the photocatalytic degradation of the dyes were proposed taking into account the synergistic effect of PANI with Bi2Se3NFs. The efficient visible-light active photocatalytic property of the polymer-inorganic composites is attributed to composites’ enhanced separation of photogenerated carriers compared to its individual constituents.