Abstract: Direct liquefaction of the cyanobacteria in ethanol under the conditions of supercritical was carried out in an autoclave.The influence of reaction temperature,reaction time,ratio of cyanobacteria to ethanol on the liquefaction were investigated.The model method was used to study the kinetics of cyanobacteria liquefaction in supercritical ethanol.The results showed that the optimal conditions were reaction temperature 270℃,reaction time 40 min,ratio of cyanobacteria to ethanol 1:15 g/mL.Under these conditions,the liquefaction conversion rate reached 83.13%.The kinetics calculation indicated that the apparent activation energy is 50.793 kJ/mol,and frequency factor is 3 437.16.