The characteristic properties of type Ⅰ (e→o+o) nocollinear phase matched LBO (LiB 3O 5) optical parametric chirped pulse amplifier are investigated. A theoretical model of noncollinear phase matched parametric process in LBO is presented. Using the numerical method, the analytical formulation for the parametric efficiency coefficient, effective gain, parametric bandwidth, gain bandwidth of the amplifier are obtained. The numerical simulation results demonstrate that not only the high gain could be obtained in this amplifier, but also the broadest gain spectrum bandwidth could be attained. It provides a great potential to efficiently femto second light pulses to generate new extremes in power, intesity and pulse duration.