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A study was conducted to compare the mean annual trends of suspended sediment concentration with the seasonal trends at two different sampling sites in the Anoia River basin, Spain, and to assess the variability of this parameter in a medium-sized Mediterranean basin with sedimentary rock types and with agriculture as the main land use. Suspended sediment samples were collected during the water years 2001-2002 and 2002-2003 at Jorba (upstream site) and Sant Sadurní (downstream site). The relationships between suspended sediment concentration and discharge showed that the general data sets were not strongly dependent on discharge, showing that other variables affect the concentration. However, the seasonal rating curves considerably improve the relationships at both sites, especially during autumn. During autumn, greater concentrations at both sites were measured. Nevertheless, these concentrations revealed larger values at the downstream site than the upstream. Higher rainfall amounts and the occurrence of larger events of greater magnitude than during spring suggest greater suspended sediment concentration during this season. In spring, the lower intensity events and the increased base flow level reduced such concentrations. The variability of suspended sediment concentration was very high at both sites and during both seasons, indicating that it is strongly related to the occurrence of flow events.