Photo-assisted electron emission from a p-type silicon field emitter array (FEA) excited by laser pulses with 405 nm wavelength is investigated for generating electron bunches at high frequency. By using a volcano structure, the photoresponse of the current pulses is less than 2 ns, which is limited by the response time of a used current amplifier. It demonstrates that an optimally designed volcano-structured silicon FEA is a promising photocathode for the applications of vacuum electronic devices based on short electron beam.