A new dynamic light scattering analysis method based on modern power spectral estimation was proposed to resolve problems on lower resolution and variance, and power spectrum leakage in the current dynamic light scattering software.The modern power spectrum estimation algorithm and measurement system were studied. Firstly, the photon correlation spectroscopic theory and the scattering spectrum estimation of dynamic light scattering measurement were introduced. Then, the dynamic scattering spectrum based on modern power spectrum estimation was descripted in detail, and the order of p was calculated particularly. Furthermore, the measurement system was described,in which the hardware components included optical systems and signal processing system and the software showed the development process. Finally, a experiment was carried out on the latex particle sample solution with the particle diameters of 30, 50, 100 nm and solution transmission of 96%. The results show that the average values of the measurement error and repeatability error are 1.88% and 1.62%, respectively,which can achieve the national standard that the measurement and repeatability errors should be less than 2%, respectively.