Fast and broadband photoelectric detection is a key process to many photoelectronic applications,during which the semiconductor light absorber plays a critical role.In this report,we prepared Cu-In-Zn-S (CIZS) nanospheres with different compositions via a facile hydrothermal method.These nanospheres were ～200 nm in size and comprised of many small nanocrystals.A photodetector responded to the visible spectrum was demonstrated by spraying the solution processed nanospheres onto gold interdigital electrodes.The photoelectric characterization of these devices revealed that ClZS nanospheres with low molar ratio of n(Cu)In(In) exhibited improved photoelectric response compared to those with high n(Cu)/n(In),which was attributed to the reduced defects.The relatively large switching ratio (ⅠonⅡoff),fast response and wide spectral coverage of the CIZS-based photodetector render it a promising potential candidate for photoelectronic applications.