3,4-diarylpyrazole derivatives were synthesized by puerarin and its alkylated derivatives through one-pot operation with hydrazine hydrate. The synthetic conditions of 3,4-diarylpyrazole derivatives were optimized, using ethanol as solvent, reating at 85 ℃ for 2 h, the yield keeps over 70%. The structures of these compounds were characterized by IR, 1H NMR,13C NMR spectra and elemental analysis. Fungicidal activities of these compounds were also evaluaed．Most of them exhibit good activities. Compound Ⅲa, Ⅲc, Ⅲf have similar or more evident antibacterial effects than that of fluconazole.