Nd2CuO4 and Nd(1.85)Ce(0.15)CiO(4-delta) single crystals with the size of phi5 mm x 25 min were successfully grown by traveling solvent floating zone (TSFZ) method. Good quality crystals can be verified by Laue back-scattering pattern, X-ray diffraction and scanning electron microscopy observation. For growth of Nd2CuO4 single crystals, pure O-2 was used as atmosphere and no superconductivity appeared; but pure O-2 and pure Ar-2 both cannot be used for growth of Nd1.85Ce0.15CuO4-delta single crystals. It is necessary to use Ar-O-2 mixed gas for growing as-grown superconductive Nd1.85Ce0.15CuO4-a single crystals without post-annealing treatment. From thermal dependence of resistivity curves, we found, with Ar-2/O-2 ratio raised, the transitional temperature for superconductivity of single crystals increased and the highest transitional temperature was 23.3 K in Nd1.85Ce0.15CuO4-delta single crystals obtained with Ar-2/O-2 ratio equal to 30/1, near to that of ceramic samples. (C) 2003 Published by Elsevier Science B.V.