This zipped file contains two excel files of high-frequency water quality data in the stream of the small forested catchment, Gozyo cattchment (12.14ha), Nara, Japan. The high-frequency on-site Water quality (WQ) measurements of K, Cl, and Na in the stream using flow-injection potentiometry method with 15-minute interval were interpolated to 10-minute interval data. The SS concentration in the stream was estimated by linear transformation from the observed 10-minute turbidity value. Table GZ_Solute gives observed 10-minute solutes data with discharge, rainfall, and temperature from 2009 to 2011, and Table GZ_Tb provides the observed 10-minute turbidity data from 2012 to 2014. SS value (mg/l) is calculated as 1.09Turbidity+6.19.The data value of -999 means missing observation.