Femtosecond optical parametric amplification is an effective means of generating broadband ultrashort pulses. First,the theoretical background of this technology is presented. Numerical simulations are carried out to show the impact of group-velocity mismatch and phase mismatch. The results suggest that phase mismatch can reduce the conversion efficiency,while group velocity can simultaneously bring down the conversion efficiency and introduce distortion to the signal pulse. Second,some progress and latest advances concerning ultrshort pulses,especially few-cycle pulses generation are reported. A specific noncollinear optical parametric amplification system used for generating 3.9 fs pulses is introduced. Supercontinuum injection,angular dispersion of pump beam and choice of operating medium are analyzed in detail. Finally,the latest achievement in acquiring high-power femtosecond pulses through this technology is presented.