Abstract: In order to improve the precision of time interval measurement in pulsed laser ranging,several interpolation methods are used.Analog interpolation time-interval measurement has advantages of high precision,small blind area,long measurement range and good linearity.Ananalog interpolation measurement method using complex programmable logic device(CPLD) and microchip was presented.Benefiting from the use of CPLD,the circuit became simplified.Furthermore,the time-interval measurement system adapted extraordinarily to high performance portable pulsed laser rangefinder for its compactness,simple structure and high reliability.