The effect of drying mode and conditions of storage on colour stability of dried onion was investigated in this work. Drying of onion at 70 or 80°C yielded brown product of unacceptable quality. A temperature up to 80°C can be applied to dry onion only for a short time, until less than 50% of water is evaporated. Then the temperature of air must be lowered to 60°C. When the stepwise change of temperature was done properly the colour stability of onion did not differ from that observed for onion dried at 60°C. Both, infrared and microwave energy promoted browning of dried onion. Moreover, the colour stability was less than that of onion dried by convection.