This paper reports a new facile one-step cyclic voltammetry electrochemical co-depositing method to prepare a novel nickel cobalt sulfide (NiCo2S4) counter electrode (CE) on a FTO glass substrate as well as its promising application as an efficient CE in CdSe quantum dot-sensitized solar cells (QD-SSCs). The QD-SSCs fabricated using NiCo2S4 as a CE exhibited a significantly enhanced short circuit current and fill factor, resulting in a significantly improved overall energy conversion efficiency (3.67%) compared to those with the Pt (2.26%), CoS (2.70%) and NiS (2.56%) CEs under 1 sun illumination. This can be attributed to the significantly enhanced electrocatalytic activity and superior electrical conductivity of the NiCo2S4 and the excellent electrical contact at the electrodeposited NiCo2S4/FTO interface. (C) 2016 The Electrochemical Society. All rights reserved.