Abstract: A back-crossing trial on Azolla that using hybrid Azolla strain Rongping 1(A. filicuioides ?A. microphylla)as male parent, A. microphylla as female parent was conducted, large amount of green seedlings and some of albino seedlings were acquired. Comparing with zymographic identification, morphological observation and physiological analysis, these seedlings were conformed as hybrid progenies. Further screening was conducted by indoor and outdoor trials on adverse condition-resistance and analysis of nutrient quality. A back-crossed strain with nice agronomic character was screened from numerous green seedlings of this hybrid combination, and named as MH3-1. The applying efficiency of MH3-1 in agricultural and husbandry production were introduced, its applying prospect in the future production of organic agriculture was analyzed.