In this study, first by using Smirnov-Kolmogorov method, the consistency of data was applied in order to optimize the relationship between water and sediment discharge rates in Amameh indicator watershed of Iran. After the consistency and authenticity of data were confirmed, by means of daily mean discharge and a software called Technical Hydrology (TH), monthly hydrograph was sketched for total period of 1969-2000 in Kamarkhani station in Amameh watershed outlet. Then, different models were tested using the equation of sediment transport and considering hydrological, climatic and biological parameters such as hydrograph situation, classification of discharge rate and the time of flow measurement. In all models, the regression relationships between the rates of water and sediment discharges were established. To choose an optimized model, the sum of the error sum of squares index was used. According to the index, the least sum of squares shows the optimized model. The results showed that the common model in which only one equation is used as a sediment rating equation has the highest error in estimation of suspended sediment. But, a model in which the data are separated based on wet and dry months and classification of the discharge rates, has the lowest error sum of squares and is considered as the optimized model.