Anisotropic quaternary Cu2ZnSnSe4 (CZTSe) semiconductor nanoparticles of kesterite phase has been developed using a single pot colloidal synthesis route. The as-synthesized non-template directed or non-seed mediated nanoparticles form stable nanoparticle ink in suitable organic solvents. The initially grown CZTSe nanoparticles of similar to 10 nm aggregated and joined into 3-dimensional anisotropic morphology. Photo-response property and photocatalytic activity of the as-synthesized CZTSe nanoparticles have been investigated. Thin films of CZTSe nanoparticle ink displayed accountable fivefold photo-current under illumination as compared to dark state. As a first case of photocatalytic application of CZTSe nanoparticles, this anisotropic CZTSe sample demonstrated effective degradation of polluting dyes for waste water treatment under indoor visible light illumination with active recyclability. (C) 2015 Elsevier B.V. All rights reserved.