A one-step strategy was designed to prepare short Ag nanorods whose aspect ratios ranges from 1.0 to 5.0 in aqueous phase without seed and template intervention. The as-prepared short Ag nanorods showed controllable longitudinal plasmon modes in visible and infrared regions. The electric-field enhancement, excitation wavelength- and excitation fluence-dependent electronic dynamics of short Ag nanorods were found adjustable. Display omitted •Short Ag nanorods synthesized using a green one-step aqueous-phase strategy.•Precise control of short Ag nanorods with aspect ratios especially from 1.0 to 5.0.•Short Ag nanorods showed tunable optical property in visible and infrared regions.•Short Ag nanorods showed tunable electric-field enhancement and electronic dynamics. Ag nanorods with finely controllable aspect ratios (especially 1–5) were synthesized in high yield via an effective one-step aqueous-phase method, in which the longitudinal plasmon modes in visible and infrared regions of short Ag nanorods were well adjustable. Meanwhile, excitation wavelength- and excitation fluence-dependent electronic dynamics of short Ag nanorods were acquired and were found to be regular. This suggested that short Ag nanorods would have great potential in plasmonic and photoelectronic fields.