Abstract: In the present paper, the authors studied the efficiency of fertilizers made from bloom forming cyanobacteria in field.Compared with efficiency of general compound fertilizes on the market, that of the organic and inorganic fertilizes from severalCyanobacteria (Microcystis) were higher to the output of tobacco, celery leek and carnation. Dose of 900kg/hm2is best in tobac2co experiments, and tobacco’ s yield, production value and fine tobacco ratio increased 7.28 %, 5.04 % and 19.81 %, respec2tively; Treated with three doses of 600kg/hm, 900kg/hm2and 1200kg/hm2, Chinese chives’output is higher than thecontrol’ s, increased 9.5 %, 17.1 % and 16.3 %, respectively; leek’ s high, leaf broad and yield increased 12. 21 % and13.32 % respectively, with treatment of 900kg/hm2, 1200 kg/hm2of Cyanobacterial fertilizer; Output of Carnation arrived to4865 bunch/100m2, increased 11.6 % compared with the control. No cyanobacterial toxin was determined in leek and soil, sug2gesting that the safety of cyanobacterial fertilizer. It not only solves the difficult problem on processing the great Cyanobacterialbiomass in some eutrophic lakes, but also improves environment, and increases benefits of society and economy.