Femtosecond laser double-pulse has important application value on the study of ultra-fast transient process area. How to realize the high accuracy of femtosecond laser pulse real-time measurement is particularly important. This paper presents a method on autocorrelation of femtosecond laser double-pulse measurement. It contains the measurement techniques of pulse interval, pulse width and the intensity ratio. Autocorrelator was used in the experiment to get the autocorrelation curve of the femtosecond laser double-pulse. The femtosecond laser double-pulse were generated by the birefringent crystal. Relying on the autocorrelation curve, the pulse interval, pulse width and the intensity ratio were got by non-linear fitting method. Contrasted the traditional cross-correlation measurement, the autocorrelation method overcome the uncertainty of the independent pulse impact on accuracy. It makes the measuring precision could be improved by more than 48% on average.