Multiangle dynamic light scattering (MDLS) technique can give better particle-size distribution (PSD) than single-angle dynamic light scattering (SDLS) technique. However, the choice of scattering angles is affected by the measuring particles in MDLS. Unimodal simulation distribution of 100 nm and 500 nm and bimodal simulation distribution of 300 nm and 600 nm are respectively measured at one, three, six and nine scattering angles and are inversed to obtain the PSD. This results show that MDLS can give better PSD with the increase of number of angles. Furthermore, the PSD has a little modification when there are more than one angle for 100 nm particles or more than three angles for 600 nm particles. A dilute bimodal suspension of polystyrene latex standard spheres mixed in a number ratio of 51 is measured at one, three, five and ten angles. The results show that one angle only can give one peak and more than three angles can give two peaks. The number ratio is closer to the true value with the increase of number of angles. Though MDLS can give better PSD than SDLS, the improvement of PSD become less obvious with the increase of number of angles. In some cases, the PSD may become worse with the increase of angle numbers because the calibration noise of scattering angle and measurement noise of light-intensity correlation function are added.