Summary. S a c c h a r o m y c e s cerevisiae was immobil-ised by adsorption to untreated sugar cane bagasse in a p a c k e d bed reactor. Complete conversion of glucose to ethanol was obtained at a dilution rate o f 0.19 h-1. Continuous ethanol production was maintained for up to 57 days. Reactor productivity increased with increasing packing density of the bagasse. Plugging of void spaces due to cell overgrowth led to channelling of the feed and decreased reactor productivity. Increasing the average column temperature alleviated plugging and restored column performance over a short period; however prolonged exposure to the high temperature resulted in decreased ethanol p r o d u c t i o n rates. Bagasse has advantages as a support material for ethanol p r o d u c t i o n from sugar cane or beet, including negligible cost, ready availability and the capacity to support a high yeast population.