Abstract: Stream hydrodynamic properties, in particular transient storage, are potential regulators of solute uptake. Little work has been done to assess parameter sensitivity of transient storage modeling over multiple spatial scales in headwater streams. The objective of the present study is to investigate characteristics of parameter sensitivity of water environmental models in the channeled headwater stream in urban areas. The headwater stream of Shiwuli River in Hefei City, Chaohu Lake Basin, was chosen as the study object. A slug field tracer experiment, in which NaCl was used as a conservative tracer, was conducted in the stream reach over combinations of four consecutive sub-reaches (63,2, 120 and 92 m below injection point). OTIS (one-dimensional transport with inflow and storage) model was used for the simulation of solute transport by view of the OTIS model code and OTIS-P optimization procedure. Each simulated stream solute concentration breakthrough curve (BTC) accurately fit to the observations. Perturbation, in which the root mean square error (RMSE) was taken as the objective function, was employed to analyze the sensitivity of the following parameters:main channel cross-sectional area A, storage zone cross-sectional area A_s, storage zone exchange coefficient α and dispersion coefficient D, with a variation of ±10% and ±20%. Results showed that the OTIS model was useful for characterizing the in-stream solute transport in the headwater of Shiwuli River. Although there was some variability in the degree of parameter sensitivity among the later three consecutive sub-reaches, a total remarkable regularity was found in the headwater stream, namely A＞α＞A_s＞D, which formed the same regular pattern as many other streams with the similar spatial scale in European and American countries. Due to the sensitivities of α and A_s being higher than that of D, the effects of transient storage on solute transport should be taken into consideration in the channeled headwater stream in urban area. In general, the results further testified to the effectiveness of perturbation method utilized above on sensitivity analysis of parameters in OTIS model.