Abstract: This paper reported on the cultivation of Bacillus thuringiensis serotypc H-14 with open solid plate medium. It was found that the toxicity of this preparation was onefold higher than that cultured in the shaking bottle. 60 batches have produced, amounting to 2,000kg. The titre of the preparatien was 600 ITU/ing. Evaluation of its mo-quitocidal effect on the spot showed that the efficacy of the preparation was similar to that of the Sandoz bacteria fluid, reducing the mosquito density to 92.6% as compared with that in a control area.