Thiophenolate-capped CdS nanocrystallites (phi-CdS, mean diameter 3.5 nm, hexagonal) were prepared and isolated as powders by reacting thiophenol in the presence of triethylamine (TEA) with CdS nanocrystallites prepared from Cd2+ and H2S in N,N-dimethylformamide (DMF). The coverage of the capping thiophenolate on the surface of CdS nanocrystallites can be controlled by varying the concentration of TEA in the preparation solution. The dispersibility giving a clear DMF solution of CdS, i.e., the solubility of phi-CdS in DMF, is well correlated with the surface coverage of thiophenolate, i.e., the solubility can be increased by increasing the coverage of thiophenolate.