Gross rainfall, throughfall and stemflow were measured in Eucalyptus globulus Labill. and Pinus pinaster Ait. stands in central Portugal over two and a half years (from January 1992 to July 1994). The results show that the interception loss is higher in the pine stand (17% of gross rainfall) than in the eucalypt stand (11% of gross rainfall). Interception loss was also simulated by the Rutter model and Gash's original analytical model, but both models overestimated the interception loss from these Mediterranean sparse forests by 29–44%. To improve the description of the rainfall interception from sparse forests, the Rutter model was reformulated. This new version of the Rutter model and a previously reformulated version of Gash's analytical model greatly improved the accuracy of the simulation for both forests, resulting in estimates of the interception loss within 3% of the measured values.