New series of 2-(aryl or alkyl)-N-phenylhydrazine-1-carboxamides 1a-j were synthesized through one-pot reactions of aldehyde or ketones, hydrazine hydrate, and phenylisocyanate in MeOH. The structure of products was confirmed by Fourier transform infrared (FT-IR), proton nuclear magnetic resonance ( 1 H NMR), and 13 C NMR spectra. Minimum inhibitory concentration (MIC) of antibacterial activity of 1a-j was screened against five bacterial strains. Compound 1f showed antibacterial activity against Pseudomonas aeruginosa and Staphylococcus aureus.