For numerical simulations by general circulation models (GCMs), it is necessary to properly describe the boundary conditions of the atmosphere; land and sea. However, the monitoring system for soil moisture and snow accumulation over land has not been well established compared to the situation over sea, where SST and sea ice concentration are operationally monitored by remote sensing. As one effort to try to estimate the global soil moisture distribution, the Global Soil Wetness Project (GSWP) was conceived. Under GSWP, the global soil moisture distribution on 1deg. x 1deg. mesh for 1987 and 1988 was simulated in an offline mode by 11 land surface models (LSMs). Even though observations and analyses were used as for forcing data, validation studies are necessary because LSMs may not simulate accurately the partitioning of water at the surface of the earth between runoff, evaporation and changes in soil moisture. Comparisons between runoff from LSMs with observed discharge were usedto validate the LSM simulations. River discharge represents integrated runoff within the drainage area, and is the only direct measurement of areal mean hydrological values available on a large scale. A gridded 1deg. x 1 deg. global river channel network, named Total Runoff Integrating Pathways (TRIP) is used to calculate mean runoff estimated by the LSMs for drainage areas upstream of 250 operational gauging stations. Runoff observations from these stations in 150 major river basins of the world have been collected for years in 1987 and 1988, and were compared with the LSM products. It was found that LSMs estimated annual runoff fairly well with a relative root mean square error of 40 [%] for drainage areas with a fairly high density of raingauge observations (> 30/10^6 sq.km) which was used to prepare the forcing precipitation. The error corresponds to approximately 18 [%] of annual evapotranspiration. LSMs are also found to have a tendency to underestimate the annual runoff. It may be caused by observational error (underestimation) of raingauges under strong wind conditions, especially for snow, as all of the LSMs underestimated the runoff for most of the drainage areas located in higher latitudes. A linear river routing model was applied for the global runoff products from the LSMs on the decad time scale from 1987 to 1988 and analyzed at 250 gauging stations. There was only a small change in annual runoff through the river routing, but the correlations between observed and simulated monthly runoff were significantly improved for most of the LSMs by introducing the routing. River runoff information was found to be effective for the validation of water cycles on the continental scale. Efforts to develop a fully coupled atmosphere-land-river-ocean model are expected in the future, and improvements to LSMs and river routing schemes are required for the goal