Silver nanoparticles colloid was prepared by pulsed laser ablation of silver target for 10 min in distilled water at different repetition rate and laser fluence to study the effect of laser ablation parameters on the silver nanoparticles colloid. Particles size, morphology and absorption spectroscopy of the obtained nanoparticles colloid were characterized by ultraviolet to visible (UV-Vis) spectrophotometer and transmission electron microscope (TEM), and the average diameter and diameter distribution were analyzed by Image-ProPlus software. The results showed that the average diameter of the silver nanoparticles prepared at repetition rate of 10 Hz and laser fluence of 4.2 J/cm2 was the smallest (D=17.54 nm), the distribution of particle size was narrowest (δ=36.86 nm) and the morphologies were fairly homogeneous. So it was confirmed that control of nanoparticles size and shape was possible by laser ablation parameters. In addition, based on the experimental results, the effects of laser ablation parameters on the silver nanoparticles colloid was discussed in terms of fragmentation and melting induced aggregation of colloidal particles by self-absorption of laser pulses.