Abstract: ZnS∶Cu,Al nanocrystals were synthesized by a hydrothermal method at 200 ℃. The photo luminescence (PL) spectra,FT-IR spectra and crystallinity of the rinsed and unrinsed samples under various molar ratios of S/Zn and effect of surfactant have been systematically investigated. The spherical-like nanocrystals had a grain size of approximately 15 nm and were well dispersed, with a zinc blende structure. Crystallization and particle size of samples decreased after the rinsed process. The PL emission intensity of unrinsed sample stronger than rinsed sample, but at low ratio of S/Zn, the enhanced emission intensity is more significantly. In addition, the surfactants also affect the surface state of nanocrystals and PL emission spectra. The results show that the luminescence mechanism of PL spectra attribute to the luminescence centers on surface of materials detected by UV light, so the surface state of nanomaterials determine the PL emission intensity and affect the crystallization of nanocrystals.