Abstract: A statistical method is proposed for calculating the frequency of a two-dimensional vector combining of discharge and sediment concentration.The method can be applied to compute the effective sediment-transporting discharge a channel reach.Using the observed discharge and sediment data from the Bayangaole station located in the Inner Mongolia reach of Yellow River during the period 1954-2006, the effective sediment-transporting discharge is calculated annually.The corresponding effective incoming sediment coefficient is also obtained.The relationships between the bank-full discharge and the effective discharge, as well as the effective incoming sediment coefficient are analyzed.The result shows that the current value of bank-full discharge at the Bayangaole station in the Inner Mongolia reach of Yellow River is affected by the antecedent discharge and sediment conditions in the previous 12 years.