Based on the working principle of pyroelectric detector,the transient response characteristics to the pulse laser of the detector were researched. The working model of pyroelectric detector single pulse radiation was built,and the model of the response used in practical application was simulated according to the material and structure parameters. The influences of the detector material properties and structural parameters on the detector response characteristics were also analyzed through simulation,in which the influences of electricity time-constant and the hot time-constant were studied mostly. Signal extraction circuits for high-repetition-frequence pulse were designed. Finally,a number of repetition frequency laser radiation experiments on the pyroelectric detector and signal extraction circuits designed were carried out. The comparative experiments on frequency response and pulse width of the detector were completed,and the feasibility of applying the pyroelectric detector to energy measurement of high-repetition-frequency and narrow pulse laser was verified. The measuring range and other index marks of the detecting unit were given.