Effects of the microwave radiation on the culture of Chlamydomonas actinochloris green flagellar alga in the stationary phase of growth are studied. After exposure to radiation at the maximum dose of 125 J/g, the cell functional state worsened but all the studied parameters were restored in 20 days and in the long run found to be even better than the control indices. The data are compared with the similar ones obtained earlier for the lag phase culture. The studied sample is found to be more resistant to the irradiation than the previous one.