Ten basins in the north of Sweden, where the hydrological model system, HBV- HMS, has been set up, were studied. The effects on the hydrological model if an approximate 20% decrease in meteorological stations occurs were studied as well as the possibility to reduce an eventual decline in model efficiency through recalibration of the model parameters. Also, an addition of stations was investigated. The results indicated that the mean reduction in model efficiency due to an approximate 20% decrease in station density was small. If the most representative stations were removed the model performance, however, decreased significantly. When a recalibration was allowed the decline in model accuracy was reduced considerably. An addition of meteorological stations gave a minor improvement in model efficiency. No significant relationships between the basin characteristics and the model sensitivity due to a change in the station network, were found.