Agricultural residues of three cultivars of castor bean ('Guarani', 'Borracha' and 'Preta') were studied to produce pulp for paper manufacture. The results showed that castor bean crops supplied a great quantity of fibrous agricultural residues. These residues have a low basic density and good macerated yield. Regarding Pinus sp. and Eucaliptus sp. fibers, the bast and woody fibers of castor bean can be reported, respectively, as long and short fibers.