In this research, CuInS2 quantum dots (QDs) have been studied as an excellent red emitting source for white LED because of its non-toxic deep red emission, and large Stokes shift properties. The CuInS2 QDs are synthesized by the one-pot method, which is a candidate for the mass-production method. In addition, formation of ZnS shells on QD surfaces has been conducted in order to reduce non-radiative recombination on its surface defects. The photoluminescence (PL) characteristics of core/shell quantum dot show that the maximum PL wavelength blue-shifts by about 80 nm on increasing its intensity more than 6 times. Quantum yield (QY) of the CuInS2/ZnS QDs shows about 67% as the maximum value. The dispersion of the quantum dots in polystyrene, which is hydrophobic and transparent, was also conducted using co-dispersing toluene. Finally, the polystyrene/quantum dot composite was applied on blue LEDs and it showed luminous efficacy of 10.7 lm/W and (0.4338, 0.1827) CIE coordinates. (C) 2011 Elsevier B.V. All rights reserved.