A novel series of (E)-N-benzylidene-4-tert-butyl-5-(1,2,4-triazol-1-yl)thiazol-2-amines have been designed and synthesized by reaction 4-tert-butyl-5-(1,2,4-triazol-1-yl)thiazol-2-amine and substituted aromatic aldehydes. Their structures were clearly established by MS, 1H NMR spectra. The crystal structure of compound 5i has been determined by X-ray diffraction analysis. The compound 5i crystal belongs to Triclinic system with space group P-1 and cell parameters: a = 0.79748(4) nm, b = 1.01803(5) nm, c = 1.14603(6) nm, α = 102.882(1)°, β = 100.253(1) °, γ = 1104.457(1)°; V = 0.850.95(7) nm3, Z = 2, Dc = 1.484 g/ cm3, F (000) = 392, R1 = 0.030, wR2 = 0.100, S = 1.10．The preliminary bioassays indicated that compound 5c exhibited 100 %, 100 % , 82.8% and 80.3% inhibition rate against G. zeae, U. virens, B. cinerea and R. solani at 25 mg/L. The compound 5d exhibited 100%, 95.5%, 100% and 100% inhibition rate against R. solani, S. scerotirum, G. zeae and U. virens) at 25 mg/L. The compound 5e exhibited 100 % inhibition rate against G. zeae . EC50 values of 5d were 1.16 mg/L, 1.38 mg/L and 1.47 mg/L against G. zeae, S. scerotirum and R. solani respectively.