Abstract Batch adsorption of T. reesei cellulase protein (1 mg ml −1–50 ml) to 10 g inorganic-based DEAE-Macrosorb has been studied under several different conditions. Approximately 70 to 80% of the protein was adsorbed in buffer at low ionic strength between pH 5.0 and 9.4 or when adsorption was carried out in distilled water. Adsorption was rapid and essentially complete after 30 min. Native polyacrylamide gel electrophoresis (PAGE) showed that major bands of protein adsorbed by DEAE-Macrosorb were recoverable by steeping the adsorbent in 2 M sodium chloride. Maximum loading of cellulase protein to DEAE-Macrosorb at pH 5.0 was approximately 14 mg g −1. After hydrolysis of Avicel or steam-exploded wood in a batch reactor, approximately 75 and 25%, respectively, of the initial cellulase protein used were recovered by adsorption to DEAE-Macrosorb and reused. The same DEAE-Macrosorb batches were used repeatedly for cellulase adsorption and may, therefore, be useful for recovery and reuse of cellulase.