Penicillium commune was grown on coffee pulp (CP) by solid-state fermentation (SSF). The effects of the duration of CP thermal treatment and the effects of incubation temperature on spore production yield were studied at laboratory scale. The effect of mixing during fermentation was assayed at pilot plant scale in a 70 L stainless steel non-aseptic reactor equipped with helical ribbons for mixing solids. For thermal treatments of CP at 121• C for 10, 20, 30 and 40 min, no significant difference in spore production yield was observed. Maximum sporulation yield was found at 25• C; when the incubation temperature was higher than 30 • C, the sporulation yield decreased significantly. A spore production yield of 3.7 × 10 9 spores g −1 dry CP was obtained when continuous mixing (0.25 rpm) was used at pilot plant scale; however, a decrease in spore yield (1.4 × 10 9 spores g −1 dry CP) was observed under static conditions. Spore production was not affected when a scale factor between 79 and 105 was assayed from laboratory to pilot plant; at this level, the productivity obtained was 3.1 × 10 7 spores g −1 dry CP h −1 . This value is similar to that found in other reports using natural substrates but working at a smaller scale.